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kernel: backport v5.8 i2c-pxa updates

Browse Source 
Add i2c-pxa updates queued for v5.8, which add bus recovery to this
driver; this is needed for the uDPU platform.

Signed-off-by: Russell King <linux@armlinux.org.uk>
This commit is contained in:
Russell King 2020-05-21 09:57:27 +01:00 committed by Petr Štetiar
parent 72a1d5c3ac
commit 714199ec34
19 changed files with 1844 additions and 0 deletions
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64
target/linux/generic/backport-5.4/803-v5.8-i2c-pxa-use-official-address-byte-helper.patch Normal file
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@ -0,0 +1,64 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 01/17] i2c: pxa: use official address byte helper
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
i2c-pxa was created before i2c_8bit_addr_from_msg() was implemented,
and used its own i2c_pxa_addr_byte() which is functionally the same.
Sadly, it was never updated to use this new helper. Switch it over.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 2c3c3d6935c0..966000923e8e 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -675,16 +675,6 @@ static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
* PXA I2C Master mode
*/
-static inline unsigned int i2c_pxa_addr_byte(struct i2c_msg *msg)
-{
- unsigned int addr = (msg->addr & 0x7f) << 1;
-
- if (msg->flags & I2C_M_RD)
- addr |= 1;
-
- return addr;
-}
-
static inline void i2c_pxa_start_message(struct pxa_i2c *i2c)
{
u32 icr;
@@ -693,8 +683,8 @@ static inline void i2c_pxa_start_message(struct pxa_i2c *i2c)
/*
* Step 1: target slave address into IDBR
*/
- writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
- i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
+ i2c->req_slave_addr = i2c_8bit_addr_from_msg(i2c->msg);
+ writel(i2c->req_slave_addr, _IDBR(i2c));
/*
* Step 2: initiate the write.
@@ -1006,8 +999,8 @@ static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
/*
* Write the next address.
*/
- writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
- i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
+ i2c->req_slave_addr = i2c_8bit_addr_from_msg(i2c->msg);
+ writel(i2c->req_slave_addr, _IDBR(i2c));
/*
* And trigger a repeated start, and send the byte.
--
2.20.1

42
target/linux/generic/backport-5.4/804-v5.8-i2c-pxa-remove-unneeded-includes.patch Normal file
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@ -0,0 +1,42 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 02/17] i2c: pxa: remove unneeded includes
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
i2c-pxa does not need linux/sched.h nor linux/time.h includes, so
remove these.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 4 ----
1 file changed, 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 966000923e8e..eddb749c9eae 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -20,8 +20,6 @@
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/init.h>
-#include <linux/time.h>
-#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
@@ -35,8 +33,6 @@
#include <linux/io.h>
#include <linux/platform_data/i2c-pxa.h>
-#include <asm/irq.h>
-
struct pxa_reg_layout {
u32 ibmr;
u32 idbr;
--
2.20.1

57
target/linux/generic/backport-5.4/805-v5.8-i2c-pxa-re-arrange-includes-to-be-in-alphabetical-or.patch Normal file
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@ -0,0 +1,57 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 03/17] i2c: pxa: re-arrange includes to be in alphabetical
order
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Arrange the includes to be in alphabetical order to help avoid
duplicated includes.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index eddb749c9eae..ee83d2e46de0 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -16,22 +16,22 @@
* Dec 2004: Added support for PXA27x and slave device probing [Liam Girdwood]
* Feb 2005: Rework slave mode handling [RMK]
*/
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/i2c.h>
-#include <linux/init.h>
+#include <linux/clk.h>
#include <linux/delay.h>
+#include <linux/err.h>
#include <linux/errno.h>
-#include <linux/interrupt.h>
+#include <linux/i2c.h>
#include <linux/i2c-pxa.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
-#include <linux/err.h>
-#include <linux/clk.h>
-#include <linux/slab.h>
-#include <linux/io.h>
#include <linux/platform_data/i2c-pxa.h>
+#include <linux/slab.h>
struct pxa_reg_layout {
u32 ibmr;
--
2.20.1

385
target/linux/generic/backport-5.4/806-v5.8-i2c-pxa-re-arrange-functions-to-flow-better.patch Normal file
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@ -0,0 +1,385 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 04/17] i2c: pxa: re-arrange functions to flow better
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Re-arrange the PXA I2C code to avoid forward declarations, and keep
similar functionality (e.g. the non-IRQ mode support) together. This
improves code readability.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 325 +++++++++++++++++------------------
1 file changed, 162 insertions(+), 163 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index ee83d2e46de0..e5f00ae39861 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -327,7 +327,6 @@ static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
#endif /* ifdef DEBUG / else */
static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
-static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
{
@@ -703,34 +702,6 @@ static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
writel(icr, _ICR(i2c));
}
-static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
-{
- /* make timeout the same as for interrupt based functions */
- long timeout = 2 * DEF_TIMEOUT;
-
- /*
- * Wait for the bus to become free.
- */
- while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
- udelay(1000);
- show_state(i2c);
- }
-
- if (timeout < 0) {
- show_state(i2c);
- dev_err(&i2c->adap.dev,
- "i2c_pxa: timeout waiting for bus free\n");
- return I2C_RETRY;
- }
-
- /*
- * Set master mode.
- */
- writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
-
- return 0;
-}
-
/*
* PXA I2C send master code
* 1. Load master code to IDBR and send it.
@@ -759,140 +730,6 @@ static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c)
return (timeout == 0) ? I2C_RETRY : 0;
}
-static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
- struct i2c_msg *msg, int num)
-{
- unsigned long timeout = 500000; /* 5 seconds */
- int ret = 0;
-
- ret = i2c_pxa_pio_set_master(i2c);
- if (ret)
- goto out;
-
- i2c->msg = msg;
- i2c->msg_num = num;
- i2c->msg_idx = 0;
- i2c->msg_ptr = 0;
- i2c->irqlogidx = 0;
-
- i2c_pxa_start_message(i2c);
-
- while (i2c->msg_num > 0 && --timeout) {
- i2c_pxa_handler(0, i2c);
- udelay(10);
- }
-
- i2c_pxa_stop_message(i2c);
-
- /*
- * We place the return code in i2c->msg_idx.
- */
- ret = i2c->msg_idx;
-
-out:
- if (timeout == 0) {
- i2c_pxa_scream_blue_murder(i2c, "timeout");
- ret = I2C_RETRY;
- }
-
- return ret;
-}
-
-/*
- * We are protected by the adapter bus mutex.
- */
-static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
-{
- long timeout;
- int ret;
-
- /*
- * Wait for the bus to become free.
- */
- ret = i2c_pxa_wait_bus_not_busy(i2c);
- if (ret) {
- dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
- goto out;
- }
-
- /*
- * Set master mode.
- */
- ret = i2c_pxa_set_master(i2c);
- if (ret) {
- dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
- goto out;
- }
-
- if (i2c->high_mode) {
- ret = i2c_pxa_send_mastercode(i2c);
- if (ret) {
- dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
- goto out;
- }
- }
-
- spin_lock_irq(&i2c->lock);
-
- i2c->msg = msg;
- i2c->msg_num = num;
- i2c->msg_idx = 0;
- i2c->msg_ptr = 0;
- i2c->irqlogidx = 0;
-
- i2c_pxa_start_message(i2c);
-
- spin_unlock_irq(&i2c->lock);
-
- /*
- * The rest of the processing occurs in the interrupt handler.
- */
- timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
- i2c_pxa_stop_message(i2c);
-
- /*
- * We place the return code in i2c->msg_idx.
- */
- ret = i2c->msg_idx;
-
- if (!timeout && i2c->msg_num) {
- i2c_pxa_scream_blue_murder(i2c, "timeout");
- ret = I2C_RETRY;
- }
-
- out:
- return ret;
-}
-
-static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
- struct i2c_msg msgs[], int num)
-{
- struct pxa_i2c *i2c = adap->algo_data;
- int ret, i;
-
- /* If the I2C controller is disabled we need to reset it
- (probably due to a suspend/resume destroying state). We do
- this here as we can then avoid worrying about resuming the
- controller before its users. */
- if (!(readl(_ICR(i2c)) & ICR_IUE))
- i2c_pxa_reset(i2c);
-
- for (i = adap->retries; i >= 0; i--) {
- ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
- if (ret != I2C_RETRY)
- goto out;
-
- if (i2c_debug)
- dev_dbg(&adap->dev, "Retrying transmission\n");
- udelay(100);
- }
- i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
- ret = -EREMOTEIO;
- out:
- i2c_pxa_set_slave(i2c, ret);
- return ret;
-}
-
/*
* i2c_pxa_master_complete - complete the message and wake up.
*/
@@ -1099,6 +936,71 @@ static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
return IRQ_HANDLED;
}
+/*
+ * We are protected by the adapter bus mutex.
+ */
+static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
+{
+ long timeout;
+ int ret;
+
+ /*
+ * Wait for the bus to become free.
+ */
+ ret = i2c_pxa_wait_bus_not_busy(i2c);
+ if (ret) {
+ dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
+ goto out;
+ }
+
+ /*
+ * Set master mode.
+ */
+ ret = i2c_pxa_set_master(i2c);
+ if (ret) {
+ dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
+ goto out;
+ }
+
+ if (i2c->high_mode) {
+ ret = i2c_pxa_send_mastercode(i2c);
+ if (ret) {
+ dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
+ goto out;
+ }
+ }
+
+ spin_lock_irq(&i2c->lock);
+
+ i2c->msg = msg;
+ i2c->msg_num = num;
+ i2c->msg_idx = 0;
+ i2c->msg_ptr = 0;
+ i2c->irqlogidx = 0;
+
+ i2c_pxa_start_message(i2c);
+
+ spin_unlock_irq(&i2c->lock);
+
+ /*
+ * The rest of the processing occurs in the interrupt handler.
+ */
+ timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
+ i2c_pxa_stop_message(i2c);
+
+ /*
+ * We place the return code in i2c->msg_idx.
+ */
+ ret = i2c->msg_idx;
+
+ if (!timeout && i2c->msg_num) {
+ i2c_pxa_scream_blue_murder(i2c, "timeout");
+ ret = I2C_RETRY;
+ }
+
+ out:
+ return ret;
+}
static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
@@ -1132,6 +1034,103 @@ static const struct i2c_algorithm i2c_pxa_algorithm = {
.functionality = i2c_pxa_functionality,
};
+/* Non-interrupt mode support */
+static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
+{
+ /* make timeout the same as for interrupt based functions */
+ long timeout = 2 * DEF_TIMEOUT;
+
+ /*
+ * Wait for the bus to become free.
+ */
+ while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
+ udelay(1000);
+ show_state(i2c);
+ }
+
+ if (timeout < 0) {
+ show_state(i2c);
+ dev_err(&i2c->adap.dev,
+ "i2c_pxa: timeout waiting for bus free\n");
+ return I2C_RETRY;
+ }
+
+ /*
+ * Set master mode.
+ */
+ writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
+
+ return 0;
+}
+
+static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
+ struct i2c_msg *msg, int num)
+{
+ unsigned long timeout = 500000; /* 5 seconds */
+ int ret = 0;
+
+ ret = i2c_pxa_pio_set_master(i2c);
+ if (ret)
+ goto out;
+
+ i2c->msg = msg;
+ i2c->msg_num = num;
+ i2c->msg_idx = 0;
+ i2c->msg_ptr = 0;
+ i2c->irqlogidx = 0;
+
+ i2c_pxa_start_message(i2c);
+
+ while (i2c->msg_num > 0 && --timeout) {
+ i2c_pxa_handler(0, i2c);
+ udelay(10);
+ }
+
+ i2c_pxa_stop_message(i2c);
+
+ /*
+ * We place the return code in i2c->msg_idx.
+ */
+ ret = i2c->msg_idx;
+
+out:
+ if (timeout == 0) {
+ i2c_pxa_scream_blue_murder(i2c, "timeout");
+ ret = I2C_RETRY;
+ }
+
+ return ret;
+}
+
+static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[], int num)
+{
+ struct pxa_i2c *i2c = adap->algo_data;
+ int ret, i;
+
+ /* If the I2C controller is disabled we need to reset it
+ (probably due to a suspend/resume destroying state). We do
+ this here as we can then avoid worrying about resuming the
+ controller before its users. */
+ if (!(readl(_ICR(i2c)) & ICR_IUE))
+ i2c_pxa_reset(i2c);
+
+ for (i = adap->retries; i >= 0; i--) {
+ ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
+ if (ret != I2C_RETRY)
+ goto out;
+
+ if (i2c_debug)
+ dev_dbg(&adap->dev, "Retrying transmission\n");
+ udelay(100);
+ }
+ i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
+ ret = -EREMOTEIO;
+ out:
+ i2c_pxa_set_slave(i2c, ret);
+ return ret;
+}
+
static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
.master_xfer = i2c_pxa_pio_xfer,
.functionality = i2c_pxa_functionality,
--
2.20.1

166
target/linux/generic/backport-5.4/807-v5.8-i2c-pxa-re-arrange-register-field-definitions.patch Normal file
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@ -0,0 +1,166 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 05/17] i2c: pxa: re-arrange register field definitions
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Arrange the register field definitions to be grouped together, rather
than the Armada-3700 definitions being separated from the rest of the
definitions.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 113 ++++++++++++++++-------------------
1 file changed, 53 insertions(+), 60 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index e5f00ae39861..ea96dfa6b9d5 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -33,6 +33,56 @@
#include <linux/platform_data/i2c-pxa.h>
#include <linux/slab.h>
+/* I2C register field definitions */
+#define ICR_START (1 << 0) /* start bit */
+#define ICR_STOP (1 << 1) /* stop bit */
+#define ICR_ACKNAK (1 << 2) /* send ACK(0) or NAK(1) */
+#define ICR_TB (1 << 3) /* transfer byte bit */
+#define ICR_MA (1 << 4) /* master abort */
+#define ICR_SCLE (1 << 5) /* master clock enable */
+#define ICR_IUE (1 << 6) /* unit enable */
+#define ICR_GCD (1 << 7) /* general call disable */
+#define ICR_ITEIE (1 << 8) /* enable tx interrupts */
+#define ICR_IRFIE (1 << 9) /* enable rx interrupts */
+#define ICR_BEIE (1 << 10) /* enable bus error ints */
+#define ICR_SSDIE (1 << 11) /* slave STOP detected int enable */
+#define ICR_ALDIE (1 << 12) /* enable arbitration interrupt */
+#define ICR_SADIE (1 << 13) /* slave address detected int enable */
+#define ICR_UR (1 << 14) /* unit reset */
+#define ICR_FM (1 << 15) /* fast mode */
+#define ICR_HS (1 << 16) /* High Speed mode */
+#define ICR_A3700_FM (1 << 16) /* fast mode for armada-3700 */
+#define ICR_A3700_HS (1 << 17) /* high speed mode for armada-3700 */
+#define ICR_GPIOEN (1 << 19) /* enable GPIO mode for SCL in HS */
+
+#define ISR_RWM (1 << 0) /* read/write mode */
+#define ISR_ACKNAK (1 << 1) /* ack/nak status */
+#define ISR_UB (1 << 2) /* unit busy */
+#define ISR_IBB (1 << 3) /* bus busy */
+#define ISR_SSD (1 << 4) /* slave stop detected */
+#define ISR_ALD (1 << 5) /* arbitration loss detected */
+#define ISR_ITE (1 << 6) /* tx buffer empty */
+#define ISR_IRF (1 << 7) /* rx buffer full */
+#define ISR_GCAD (1 << 8) /* general call address detected */
+#define ISR_SAD (1 << 9) /* slave address detected */
+#define ISR_BED (1 << 10) /* bus error no ACK/NAK */
+
+#define ILCR_SLV_SHIFT 0
+#define ILCR_SLV_MASK (0x1FF << ILCR_SLV_SHIFT)
+#define ILCR_FLV_SHIFT 9
+#define ILCR_FLV_MASK (0x1FF << ILCR_FLV_SHIFT)
+#define ILCR_HLVL_SHIFT 18
+#define ILCR_HLVL_MASK (0x1FF << ILCR_HLVL_SHIFT)
+#define ILCR_HLVH_SHIFT 27
+#define ILCR_HLVH_MASK (0x1F << ILCR_HLVH_SHIFT)
+
+#define IWCR_CNT_SHIFT 0
+#define IWCR_CNT_MASK (0x1F << IWCR_CNT_SHIFT)
+#define IWCR_HS_CNT1_SHIFT 5
+#define IWCR_HS_CNT1_MASK (0x1F << IWCR_HS_CNT1_SHIFT)
+#define IWCR_HS_CNT2_SHIFT 10
+#define IWCR_HS_CNT2_MASK (0x1F << IWCR_HS_CNT2_SHIFT)
+
struct pxa_reg_layout {
u32 ibmr;
u32 idbr;
@@ -53,12 +103,7 @@ enum pxa_i2c_types {
REGS_A3700,
};
-#define ICR_BUSMODE_FM (1 << 16) /* shifted fast mode for armada-3700 */
-#define ICR_BUSMODE_HS (1 << 17) /* shifted high speed mode for armada-3700 */
-
-/*
- * I2C registers definitions
- */
+/* I2C register layout definitions */
static struct pxa_reg_layout pxa_reg_layout[] = {
[REGS_PXA2XX] = {
.ibmr = 0x00,
@@ -96,8 +141,8 @@ static struct pxa_reg_layout pxa_reg_layout[] = {
.icr = 0x08,
.isr = 0x0c,
.isar = 0x10,
- .fm = ICR_BUSMODE_FM,
- .hs = ICR_BUSMODE_HS,
+ .fm = ICR_A3700_FM,
+ .hs = ICR_A3700_HS,
},
};
@@ -111,58 +156,6 @@ static const struct platform_device_id i2c_pxa_id_table[] = {
};
MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
-/*
- * I2C bit definitions
- */
-
-#define ICR_START (1 << 0) /* start bit */
-#define ICR_STOP (1 << 1) /* stop bit */
-#define ICR_ACKNAK (1 << 2) /* send ACK(0) or NAK(1) */
-#define ICR_TB (1 << 3) /* transfer byte bit */
-#define ICR_MA (1 << 4) /* master abort */
-#define ICR_SCLE (1 << 5) /* master clock enable */
-#define ICR_IUE (1 << 6) /* unit enable */
-#define ICR_GCD (1 << 7) /* general call disable */
-#define ICR_ITEIE (1 << 8) /* enable tx interrupts */
-#define ICR_IRFIE (1 << 9) /* enable rx interrupts */
-#define ICR_BEIE (1 << 10) /* enable bus error ints */
-#define ICR_SSDIE (1 << 11) /* slave STOP detected int enable */
-#define ICR_ALDIE (1 << 12) /* enable arbitration interrupt */
-#define ICR_SADIE (1 << 13) /* slave address detected int enable */
-#define ICR_UR (1 << 14) /* unit reset */
-#define ICR_FM (1 << 15) /* fast mode */
-#define ICR_HS (1 << 16) /* High Speed mode */
-#define ICR_GPIOEN (1 << 19) /* enable GPIO mode for SCL in HS */
-
-#define ISR_RWM (1 << 0) /* read/write mode */
-#define ISR_ACKNAK (1 << 1) /* ack/nak status */
-#define ISR_UB (1 << 2) /* unit busy */
-#define ISR_IBB (1 << 3) /* bus busy */
-#define ISR_SSD (1 << 4) /* slave stop detected */
-#define ISR_ALD (1 << 5) /* arbitration loss detected */
-#define ISR_ITE (1 << 6) /* tx buffer empty */
-#define ISR_IRF (1 << 7) /* rx buffer full */
-#define ISR_GCAD (1 << 8) /* general call address detected */
-#define ISR_SAD (1 << 9) /* slave address detected */
-#define ISR_BED (1 << 10) /* bus error no ACK/NAK */
-
-/* bit field shift & mask */
-#define ILCR_SLV_SHIFT 0
-#define ILCR_SLV_MASK (0x1FF << ILCR_SLV_SHIFT)
-#define ILCR_FLV_SHIFT 9
-#define ILCR_FLV_MASK (0x1FF << ILCR_FLV_SHIFT)
-#define ILCR_HLVL_SHIFT 18
-#define ILCR_HLVL_MASK (0x1FF << ILCR_HLVL_SHIFT)
-#define ILCR_HLVH_SHIFT 27
-#define ILCR_HLVH_MASK (0x1F << ILCR_HLVH_SHIFT)
-
-#define IWCR_CNT_SHIFT 0
-#define IWCR_CNT_MASK (0x1F << IWCR_CNT_SHIFT)
-#define IWCR_HS_CNT1_SHIFT 5
-#define IWCR_HS_CNT1_MASK (0x1F << IWCR_HS_CNT1_SHIFT)
-#define IWCR_HS_CNT2_SHIFT 10
-#define IWCR_HS_CNT2_MASK (0x1F << IWCR_HS_CNT2_SHIFT)
-
struct pxa_i2c {
spinlock_t lock;
wait_queue_head_t wait;
--
2.20.1

71
target/linux/generic/backport-5.4/808-v5.8-i2c-pxa-add-and-use-definitions-for-IBMR-register.patch Normal file
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@ -0,0 +1,71 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 06/17] i2c: pxa: add and use definitions for IBMR register
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Add definitions for the bits in the IBMR register, and use them in the
code. This improves readability.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index ea96dfa6b9d5..b3286d7ab75d 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -34,6 +34,9 @@
#include <linux/slab.h>
/* I2C register field definitions */
+#define IBMR_SDAS (1 << 0)
+#define IBMR_SCLS (1 << 1)
+
#define ICR_START (1 << 0) /* start bit */
#define ICR_STOP (1 << 1) /* stop bit */
#define ICR_ACKNAK (1 << 2) /* send ACK(0) or NAK(1) */
@@ -335,7 +338,7 @@ static void i2c_pxa_abort(struct pxa_i2c *i2c)
return;
}
- while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) {
+ while ((i > 0) && (readl(_IBMR(i2c)) & IBMR_SDAS) == 0) {
unsigned long icr = readl(_ICR(i2c));
icr &= ~ICR_START;
@@ -390,7 +393,8 @@ static int i2c_pxa_wait_master(struct pxa_i2c *i2c)
* quick check of the i2c lines themselves to ensure they've
* gone high...
*/
- if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) == 0 && readl(_IBMR(i2c)) == 3) {
+ if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) == 0 &&
+ readl(_IBMR(i2c)) == (IBMR_SCLS | IBMR_SDAS)) {
if (i2c_debug > 0)
dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
return 1;
@@ -575,7 +579,7 @@ static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
timeout = 0x10000;
while (1) {
- if ((readl(_IBMR(i2c)) & 2) == 2)
+ if ((readl(_IBMR(i2c)) & IBMR_SCLS) == IBMR_SCLS)
break;
timeout--;
@@ -638,7 +642,7 @@ static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
timeout = 0x10000;
while (1) {
- if ((readl(_IBMR(i2c)) & 2) == 2)
+ if ((readl(_IBMR(i2c)) & IBMR_SCLS) == IBMR_SCLS)
break;
timeout--;
--
2.20.1

71
target/linux/generic/backport-5.4/809-v5.8-i2c-pxa-always-set-fm-and-hs-members-for-each-type.patch Normal file
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@ -0,0 +1,71 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 07/17] i2c: pxa: always set fm and hs members for each type
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Always set the fm and hs members of struct pxa_reg_layout. These
members are already taking space, we don't need code as well.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index b3286d7ab75d..05dbe6bf4633 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -114,6 +114,8 @@ static struct pxa_reg_layout pxa_reg_layout[] = {
.icr = 0x10,
.isr = 0x18,
.isar = 0x20,
+ .fm = ICR_FM,
+ .hs = ICR_HS,
},
[REGS_PXA3XX] = {
.ibmr = 0x00,
@@ -121,6 +123,8 @@ static struct pxa_reg_layout pxa_reg_layout[] = {
.icr = 0x08,
.isr = 0x0c,
.isar = 0x10,
+ .fm = ICR_FM,
+ .hs = ICR_HS,
},
[REGS_CE4100] = {
.ibmr = 0x14,
@@ -128,6 +132,8 @@ static struct pxa_reg_layout pxa_reg_layout[] = {
.icr = 0x00,
.isr = 0x04,
/* no isar register */
+ .fm = ICR_FM,
+ .hs = ICR_HS,
},
[REGS_PXA910] = {
.ibmr = 0x00,
@@ -137,6 +143,8 @@ static struct pxa_reg_layout pxa_reg_layout[] = {
.isar = 0x20,
.ilcr = 0x28,
.iwcr = 0x30,
+ .fm = ICR_FM,
+ .hs = ICR_HS,
},
[REGS_A3700] = {
.ibmr = 0x00,
@@ -1235,8 +1243,8 @@ static int i2c_pxa_probe(struct platform_device *dev)
i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
- i2c->fm_mask = pxa_reg_layout[i2c_type].fm ? : ICR_FM;
- i2c->hs_mask = pxa_reg_layout[i2c_type].hs ? : ICR_HS;
+ i2c->fm_mask = pxa_reg_layout[i2c_type].fm;
+ i2c->hs_mask = pxa_reg_layout[i2c_type].hs;
if (i2c_type != REGS_CE4100)
i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
--
2.20.1

135
target/linux/generic/backport-5.4/810-v5.8-i2c-pxa-move-private-definitions-to-i2c-pxa.c.patch Normal file
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@ -0,0 +1,135 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 08/17] i2c: pxa: move private definitions to i2c-pxa.c
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Move driver-private definitions out of the i2c-pxa.h platform data
header file into the driver itself. Nothing outside of the driver
makes use of these constants.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 43 ++++++++++++++++++++++++
include/linux/platform_data/i2c-pxa.h | 48 ---------------------------
2 files changed, 43 insertions(+), 48 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 05dbe6bf4633..482768a9fdd2 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -86,6 +86,49 @@
#define IWCR_HS_CNT2_SHIFT 10
#define IWCR_HS_CNT2_MASK (0x1F << IWCR_HS_CNT2_SHIFT)
+/* need a longer timeout if we're dealing with the fact we may well be
+ * looking at a multi-master environment
+ */
+#define DEF_TIMEOUT 32
+
+#define BUS_ERROR (-EREMOTEIO)
+#define XFER_NAKED (-ECONNREFUSED)
+#define I2C_RETRY (-2000) /* an error has occurred retry transmit */
+
+/* ICR initialize bit values
+ *
+ * 15 FM 0 (100 kHz operation)
+ * 14 UR 0 (No unit reset)
+ * 13 SADIE 0 (Disables the unit from interrupting on slave addresses
+ * matching its slave address)
+ * 12 ALDIE 0 (Disables the unit from interrupt when it loses arbitration
+ * in master mode)
+ * 11 SSDIE 0 (Disables interrupts from a slave stop detected, in slave mode)
+ * 10 BEIE 1 (Enable interrupts from detected bus errors, no ACK sent)
+ * 9 IRFIE 1 (Enable interrupts from full buffer received)
+ * 8 ITEIE 1 (Enables the I2C unit to interrupt when transmit buffer empty)
+ * 7 GCD 1 (Disables i2c unit response to general call messages as a slave)
+ * 6 IUE 0 (Disable unit until we change settings)
+ * 5 SCLE 1 (Enables the i2c clock output for master mode (drives SCL)
+ * 4 MA 0 (Only send stop with the ICR stop bit)
+ * 3 TB 0 (We are not transmitting a byte initially)
+ * 2 ACKNAK 0 (Send an ACK after the unit receives a byte)
+ * 1 STOP 0 (Do not send a STOP)
+ * 0 START 0 (Do not send a START)
+ */
+#define I2C_ICR_INIT (ICR_BEIE | ICR_IRFIE | ICR_ITEIE | ICR_GCD | ICR_SCLE)
+
+/* I2C status register init values
+ *
+ * 10 BED 1 (Clear bus error detected)
+ * 9 SAD 1 (Clear slave address detected)
+ * 7 IRF 1 (Clear IDBR Receive Full)
+ * 6 ITE 1 (Clear IDBR Transmit Empty)
+ * 5 ALD 1 (Clear Arbitration Loss Detected)
+ * 4 SSD 1 (Clear Slave Stop Detected)
+ */
+#define I2C_ISR_INIT 0x7FF /* status register init */
+
struct pxa_reg_layout {
u32 ibmr;
u32 idbr;
diff --git a/include/linux/platform_data/i2c-pxa.h b/include/linux/platform_data/i2c-pxa.h
index cb290092599c..5c08a6ff3444 100644
--- a/include/linux/platform_data/i2c-pxa.h
+++ b/include/linux/platform_data/i2c-pxa.h
@@ -7,54 +7,6 @@
#ifndef _I2C_PXA_H_
#define _I2C_PXA_H_
-#if 0
-#define DEF_TIMEOUT 3
-#else
-/* need a longer timeout if we're dealing with the fact we may well be
- * looking at a multi-master environment
-*/
-#define DEF_TIMEOUT 32
-#endif
-
-#define BUS_ERROR (-EREMOTEIO)
-#define XFER_NAKED (-ECONNREFUSED)
-#define I2C_RETRY (-2000) /* an error has occurred retry transmit */
-
-/* ICR initialize bit values
-*
-* 15. FM 0 (100 Khz operation)
-* 14. UR 0 (No unit reset)
-* 13. SADIE 0 (Disables the unit from interrupting on slave addresses
-* matching its slave address)
-* 12. ALDIE 0 (Disables the unit from interrupt when it loses arbitration
-* in master mode)
-* 11. SSDIE 0 (Disables interrupts from a slave stop detected, in slave mode)
-* 10. BEIE 1 (Enable interrupts from detected bus errors, no ACK sent)
-* 9. IRFIE 1 (Enable interrupts from full buffer received)
-* 8. ITEIE 1 (Enables the I2C unit to interrupt when transmit buffer empty)
-* 7. GCD 1 (Disables i2c unit response to general call messages as a slave)
-* 6. IUE 0 (Disable unit until we change settings)
-* 5. SCLE 1 (Enables the i2c clock output for master mode (drives SCL)
-* 4. MA 0 (Only send stop with the ICR stop bit)
-* 3. TB 0 (We are not transmitting a byte initially)
-* 2. ACKNAK 0 (Send an ACK after the unit receives a byte)
-* 1. STOP 0 (Do not send a STOP)
-* 0. START 0 (Do not send a START)
-*
-*/
-#define I2C_ICR_INIT (ICR_BEIE | ICR_IRFIE | ICR_ITEIE | ICR_GCD | ICR_SCLE)
-
-/* I2C status register init values
- *
- * 10. BED 1 (Clear bus error detected)
- * 9. SAD 1 (Clear slave address detected)
- * 7. IRF 1 (Clear IDBR Receive Full)
- * 6. ITE 1 (Clear IDBR Transmit Empty)
- * 5. ALD 1 (Clear Arbitration Loss Detected)
- * 4. SSD 1 (Clear Slave Stop Detected)
- */
-#define I2C_ISR_INIT 0x7FF /* status register init */
-
struct i2c_slave_client;
struct i2c_pxa_platform_data {
--
2.20.1

55
target/linux/generic/backport-5.4/811-v5.8-i2c-pxa-move-DT-IDs-along-side-platform-IDs.patch Normal file
View File

@ -0,0 +1,55 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 09/17] i2c: pxa: move DT IDs along side platform IDs
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Move the ID tables into one place, near the device dependent data.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 482768a9fdd2..760a29fb6af5 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -200,6 +200,15 @@ static struct pxa_reg_layout pxa_reg_layout[] = {
},
};
+static const struct of_device_id i2c_pxa_dt_ids[] = {
+ { .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
+ { .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
+ { .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 },
+ { .compatible = "marvell,armada-3700-i2c", .data = (void *)REGS_A3700 },
+ {}
+};
+MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
+
static const struct platform_device_id i2c_pxa_id_table[] = {
{ "pxa2xx-i2c", REGS_PXA2XX },
{ "pxa3xx-pwri2c", REGS_PXA3XX },
@@ -1184,15 +1193,6 @@ static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
.functionality = i2c_pxa_functionality,
};
-static const struct of_device_id i2c_pxa_dt_ids[] = {
- { .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
- { .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
- { .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 },
- { .compatible = "marvell,armada-3700-i2c", .data = (void *)REGS_A3700 },
- {}
-};
-MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
-
static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c,
enum pxa_i2c_types *i2c_types)
{
--
2.20.1

52
target/linux/generic/backport-5.4/812-v5.8-i2c-pxa-fix-i2c_pxa_scream_blue_murder-debug-output.patch Normal file
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@ -0,0 +1,52 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 10/17] i2c: pxa: fix i2c_pxa_scream_blue_murder() debug output
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
The IRQ log output is supposed to appear on a single line. However,
commit 3a2dc1677b60 ("i2c: pxa: Update debug function to dump more info
on error") resulted in it being printed one-entry-per-line, which is
excessively long.
Fixing this is not a trivial matter; using pr_cont() doesn't work as
the previous dev_dbg() may not have been compiled in, or may be
dynamic.
Since the rest of this function output is at error level, and is also
debug output, promote this to error level as well to avoid this
problem.
Reduce the number of always zero prefix digits to save screen real-
estate.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 760a29fb6af5..f3a11050053c 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -364,11 +364,10 @@ static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
dev_err(dev, "IBMR: %08x IDBR: %08x ICR: %08x ISR: %08x\n",
readl(_IBMR(i2c)), readl(_IDBR(i2c)), readl(_ICR(i2c)),
readl(_ISR(i2c)));
- dev_dbg(dev, "log: ");
+ dev_err(dev, "log:");
for (i = 0; i < i2c->irqlogidx; i++)
- pr_debug("[%08x:%08x] ", i2c->isrlog[i], i2c->icrlog[i]);
-
- pr_debug("\n");
+ pr_cont(" [%03x:%05x]", i2c->isrlog[i], i2c->icrlog[i]);
+ pr_cont("\n");
}
#else /* ifdef DEBUG */
--
2.20.1

58
target/linux/generic/backport-5.4/813-v5.8-i2c-pxa-clean-up-decode_bits.patch Normal file
View File

@ -0,0 +1,58 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 11/17] i2c: pxa: clean up decode_bits()
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Clean up decode_bits() to use pr_cont(), and move the newline into the
function rather than at its two callsites. Avoid printing an
unnecessary space before the newline.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index f3a11050053c..b2c7765756e2 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -287,13 +287,14 @@ struct bits {
static inline void
decode_bits(const char *prefix, const struct bits *bits, int num, u32 val)
{
- printk("%s %08x: ", prefix, val);
+ printk("%s %08x:", prefix, val);
while (num--) {
const char *str = val & bits->mask ? bits->set : bits->unset;
if (str)
- printk("%s ", str);
+ pr_cont(" %s", str);
bits++;
}
+ pr_cont("\n");
}
static const struct bits isr_bits[] = {
@@ -313,7 +314,6 @@ static const struct bits isr_bits[] = {
static void decode_ISR(unsigned int val)
{
decode_bits(KERN_DEBUG "ISR", isr_bits, ARRAY_SIZE(isr_bits), val);
- printk("\n");
}
static const struct bits icr_bits[] = {
@@ -338,7 +338,6 @@ static const struct bits icr_bits[] = {
static void decode_ICR(unsigned int val)
{
decode_bits(KERN_DEBUG "ICR", icr_bits, ARRAY_SIZE(icr_bits), val);
- printk("\n");
}
#endif
--
2.20.1

58
target/linux/generic/backport-5.4/814-v5.8-i2c-pxa-fix-i2c_pxa_wait_bus_not_busy-boundary-condi.patch Normal file
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@ -0,0 +1,58 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Cc: linux-i2c@vger.kernel.org
Subject: [PATCH 12/17] i2c: pxa: fix i2c_pxa_wait_bus_not_busy() boundary
condition
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Fix i2c_pxa_wait_bus_not_busy()'s boundary conditions, so that a
coincidental success and timeout results in the function returning
success.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index b2c7765756e2..19505ffbb8f1 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -417,19 +417,26 @@ static void i2c_pxa_abort(struct pxa_i2c *i2c)
static int i2c_pxa_wait_bus_not_busy(struct pxa_i2c *i2c)
{
int timeout = DEF_TIMEOUT;
+ u32 isr;
- while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
- if ((readl(_ISR(i2c)) & ISR_SAD) != 0)
+ while (1) {
+ isr = readl(_ISR(i2c));
+ if (!(isr & (ISR_IBB | ISR_UB)))
+ return 0;
+
+ if (isr & ISR_SAD)
timeout += 4;
+ if (!timeout--)
+ break;
+
msleep(2);
show_state(i2c);
}
- if (timeout < 0)
- show_state(i2c);
+ show_state(i2c);
- return timeout < 0 ? I2C_RETRY : 0;
+ return I2C_RETRY;
}
static int i2c_pxa_wait_master(struct pxa_i2c *i2c)
--
2.20.1

96
target/linux/generic/backport-5.4/815-v5.8-i2c-pxa-consolidate-i2c_pxa_-xfer-implementations.patch Normal file
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@ -0,0 +1,96 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 1/7] i2c: pxa: consolidate i2c_pxa_*xfer() implementations
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Most of i2c_pxa_pio_xfer() and i2c_pxa_xfer() are identical; the only
differences are that i2c_pxa_pio_xfer() may reset the bus, and they
use different underlying transfer functions. The retry loop is the
same. Consolidate these two functions.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 36 ++++++++++++++++--------------------
1 file changed, 16 insertions(+), 20 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index c1e50c0b9756..46f1cf97d955 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -1102,18 +1102,20 @@ static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
return ret;
}
-static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+static int i2c_pxa_internal_xfer(struct pxa_i2c *i2c,
+ struct i2c_msg *msgs, int num,
+ int (*xfer)(struct pxa_i2c *,
+ struct i2c_msg *, int num))
{
- struct pxa_i2c *i2c = adap->algo_data;
int ret, i;
- for (i = adap->retries; i >= 0; i--) {
- ret = i2c_pxa_do_xfer(i2c, msgs, num);
+ for (i = i2c->adap.retries; i >= 0; i--) {
+ ret = xfer(i2c, msgs, num);
if (ret != I2C_RETRY)
goto out;
if (i2c_debug)
- dev_dbg(&adap->dev, "Retrying transmission\n");
+ dev_dbg(&i2c->adap.dev, "Retrying transmission\n");
udelay(100);
}
i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
@@ -1123,6 +1125,14 @@ static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num
return ret;
}
+static int i2c_pxa_xfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[], int num)
+{
+ struct pxa_i2c *i2c = adap->algo_data;
+
+ return i2c_pxa_internal_xfer(i2c, msgs, num, i2c_pxa_do_xfer);
+}
+
static u32 i2c_pxa_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
@@ -1210,7 +1220,6 @@ static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
struct i2c_msg msgs[], int num)
{
struct pxa_i2c *i2c = adap->algo_data;
- int ret, i;
/* If the I2C controller is disabled we need to reset it
(probably due to a suspend/resume destroying state). We do
@@ -1219,20 +1228,7 @@ static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
if (!(readl(_ICR(i2c)) & ICR_IUE))
i2c_pxa_reset(i2c);
- for (i = adap->retries; i >= 0; i--) {
- ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
- if (ret != I2C_RETRY)
- goto out;
-
- if (i2c_debug)
- dev_dbg(&adap->dev, "Retrying transmission\n");
- udelay(100);
- }
- i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
- ret = -EREMOTEIO;
- out:
- i2c_pxa_set_slave(i2c, ret);
- return ret;
+ return i2c_pxa_internal_xfer(i2c, msgs, num, i2c_pxa_do_pio_xfer);
}
static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
--
2.20.1

72
target/linux/generic/backport-5.4/816-v5.8-i2c-pxa-avoid-complaints-with-non-responsive-slaves.patch Normal file
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@ -0,0 +1,72 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 2/7] i2c: pxa: avoid complaints with non-responsive slaves
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Running i2cdetect on a PXA I2C adapter is very noisy; it complains
whenever a slave fails to respond to the address cycle. Since it is
normal to probe for slaves in this way, we should not fill the kernel
log. This is especially true with SFP modules that take a while to
respond on the I2C bus, and probing via the I2C bus is the only way to
detect that they are ready.
Fix this by changing the internal transfer return code from I2C_RETRY
to a new NO_SLAVE code (mapped to -ENXIO, as per the I2C documentation
for this condition, but we still return -EREMOTEIO to the I2C stack to
maintain long established driver behaviour.)
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 46f1cf97d955..f20f8b905793 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -90,6 +90,7 @@
*/
#define DEF_TIMEOUT 32
+#define NO_SLAVE (-ENXIO)
#define BUS_ERROR (-EREMOTEIO)
#define XFER_NAKED (-ECONNREFUSED)
#define I2C_RETRY (-2000) /* an error has occurred retry transmit */
@@ -881,7 +882,7 @@ static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
*/
if (isr & ISR_ACKNAK) {
if (i2c->msg_ptr == 0 && i2c->msg_idx == 0)
- ret = I2C_RETRY;
+ ret = NO_SLAVE;
else
ret = XFER_NAKED;
}
@@ -1109,16 +1110,19 @@ static int i2c_pxa_internal_xfer(struct pxa_i2c *i2c,
{
int ret, i;
- for (i = i2c->adap.retries; i >= 0; i--) {
+ for (i = 0; ; ) {
ret = xfer(i2c, msgs, num);
- if (ret != I2C_RETRY)
+ if (ret != I2C_RETRY && ret != NO_SLAVE)
goto out;
+ if (++i >= i2c->adap.retries)
+ break;
if (i2c_debug)
dev_dbg(&i2c->adap.dev, "Retrying transmission\n");
udelay(100);
}
- i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
+ if (ret != NO_SLAVE)
+ i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
ret = -EREMOTEIO;
out:
i2c_pxa_set_slave(i2c, ret);
--
2.20.1

50
target/linux/generic/backport-5.4/817-v5.8-i2c-pxa-ensure-timeout-messages-are-unique.patch Normal file
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@ -0,0 +1,50 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 3/7] i2c: pxa: ensure timeout messages are unique
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Ensure that the various timeout messages can identify where in the code
they were produced from to aid debugging.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index f20f8b905793..0becab239476 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -1095,7 +1095,7 @@ static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
ret = i2c->msg_idx;
if (!timeout && i2c->msg_num) {
- i2c_pxa_scream_blue_murder(i2c, "timeout");
+ i2c_pxa_scream_blue_murder(i2c, "timeout with active message");
ret = I2C_RETRY;
}
@@ -1169,7 +1169,7 @@ static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
if (timeout < 0) {
show_state(i2c);
dev_err(&i2c->adap.dev,
- "i2c_pxa: timeout waiting for bus free\n");
+ "i2c_pxa: timeout waiting for bus free (set_master)\n");
return I2C_RETRY;
}
@@ -1213,7 +1213,7 @@ static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
out:
if (timeout == 0) {
- i2c_pxa_scream_blue_murder(i2c, "timeout");
+ i2c_pxa_scream_blue_murder(i2c, "timeout (do_pio_xfer)");
ret = I2C_RETRY;
}
--
2.20.1

39
target/linux/generic/backport-5.4/818-v5.8-i2c-pxa-remove-some-unnecessary-debug.patch Normal file
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@ -0,0 +1,39 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 4/7] i2c: pxa: remove some unnecessary debug
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Remove unnecessary show_state() in the loop inside
i2c_pxa_pio_set_master(), which can be unnecessarily verbose.
Remove the i2c_pxa_scream_blue_murder() in i2c_pxa_pio_xfer(), which
will trigger if we are probing the I2C bus and a slave does not
respond; this is a normal event, and not something to report.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 0becab239476..db739cce93ac 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -1161,10 +1161,8 @@ static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
/*
* Wait for the bus to become free.
*/
- while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
+ while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB))
udelay(1000);
- show_state(i2c);
- }
if (timeout < 0) {
show_state(i2c);
--
2.20.1

43
target/linux/generic/backport-5.4/819-v5.8-i2c-pxa-clear-all-master-action-bits-in-i2c_pxa_stop.patch Normal file
View File

@ -0,0 +1,43 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 5/7] i2c: pxa: clear all master action bits in
i2c_pxa_stop_message()
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
If we timeout during a message transfer, the control register may
contain bits that cause an action to be set. Read-modify-writing the
register leaving these bits set may trigger the hardware to attempt
one of these actions unintentionally.
Always clear these bits when cleaning up after a message or after
a timeout.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index db739cce93ac..a72d07bdb793 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -795,11 +795,9 @@ static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
{
u32 icr;
- /*
- * Clear the STOP and ACK flags
- */
+ /* Clear the START, STOP, ACK, TB and MA flags */
icr = readl(_ICR(i2c));
- icr &= ~(ICR_STOP | ICR_ACKNAK);
+ icr &= ~(ICR_START | ICR_STOP | ICR_ACKNAK | ICR_TB | ICR_MA);
writel(icr, _ICR(i2c));
}
--
2.20.1

40
target/linux/generic/backport-5.4/820-v5.8-i2c-pxa-use-master-abort-for-device-probes.patch Normal file
View File

@ -0,0 +1,40 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 6/7] i2c: pxa: use master-abort for device probes
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Use master-abort to send the stop condition after an address cycle
rather than resetting the controller.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index a72d07bdb793..0e194d6cd1b5 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -940,14 +940,8 @@ static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
icr &= ~ICR_ALDIE;
icr |= ICR_START | ICR_TB;
} else {
- if (i2c->msg->len == 0) {
- /*
- * Device probes have a message length of zero
- * and need the bus to be reset before it can
- * be used again.
- */
- i2c_pxa_reset(i2c);
- }
+ if (i2c->msg->len == 0)
+ icr |= ICR_MA;
i2c_pxa_master_complete(i2c, 0);
}
--
2.20.1

290
target/linux/generic/backport-5.4/821-v5.8-i2c-pxa-implement-generic-i2c-bus-recovery.patch Normal file
View File

@ -0,0 +1,290 @@
From: Russell King <rmk+kernel@armlinux.org.uk>
Bcc: linux@mail.armlinux.org.uk
Subject: [PATCH 7/7] i2c: pxa: implement generic i2c bus recovery
MIME-Version: 1.0
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
Implement generic GPIO-based I2C bus recovery for the PXA I2C driver.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/i2c/busses/i2c-pxa.c | 176 +++++++++++++++++++++++++++++++----
1 file changed, 159 insertions(+), 17 deletions(-)
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 0e194d6cd1b5..a7885b8b5031 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -20,6 +20,7 @@
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/errno.h>
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
@@ -28,6 +29,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/platform_data/i2c-pxa.h>
#include <linux/slab.h>
@@ -260,6 +262,11 @@ struct pxa_i2c {
bool highmode_enter;
u32 fm_mask;
u32 hs_mask;
+
+ struct i2c_bus_recovery_info recovery;
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pinctrl_default;
+ struct pinctrl_state *pinctrl_recovery;
};
#define _IBMR(i2c) ((i2c)->reg_ibmr)
@@ -559,13 +566,8 @@ static void i2c_pxa_set_slave(struct pxa_i2c *i2c, int errcode)
#define i2c_pxa_set_slave(i2c, err) do { } while (0)
#endif
-static void i2c_pxa_reset(struct pxa_i2c *i2c)
+static void i2c_pxa_do_reset(struct pxa_i2c *i2c)
{
- pr_debug("Resetting I2C Controller Unit\n");
-
- /* abort any transfer currently under way */
- i2c_pxa_abort(i2c);
-
/* reset according to 9.8 */
writel(ICR_UR, _ICR(i2c));
writel(I2C_ISR_INIT, _ISR(i2c));
@@ -584,12 +586,25 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c)
#endif
i2c_pxa_set_slave(i2c, 0);
+}
+static void i2c_pxa_enable(struct pxa_i2c *i2c)
+{
/* enable unit */
writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c));
udelay(100);
}
+static void i2c_pxa_reset(struct pxa_i2c *i2c)
+{
+ pr_debug("Resetting I2C Controller Unit\n");
+
+ /* abort any transfer currently under way */
+ i2c_pxa_abort(i2c);
+ i2c_pxa_do_reset(i2c);
+ i2c_pxa_enable(i2c);
+}
+
#ifdef CONFIG_I2C_PXA_SLAVE
/*
@@ -1043,6 +1058,7 @@ static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
ret = i2c_pxa_wait_bus_not_busy(i2c);
if (ret) {
dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
+ i2c_recover_bus(&i2c->adap);
goto out;
}
@@ -1088,6 +1104,7 @@ static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
if (!timeout && i2c->msg_num) {
i2c_pxa_scream_blue_murder(i2c, "timeout with active message");
+ i2c_recover_bus(&i2c->adap);
ret = I2C_RETRY;
}
@@ -1277,6 +1294,129 @@ static int i2c_pxa_probe_pdata(struct platform_device *pdev,
return 0;
}
+static void i2c_pxa_prepare_recovery(struct i2c_adapter *adap)
+{
+ struct pxa_i2c *i2c = adap->algo_data;
+ u32 ibmr = readl(_IBMR(i2c));
+
+ /*
+ * Program the GPIOs to reflect the current I2C bus state while
+ * we transition to recovery; this avoids glitching the bus.
+ */
+ gpiod_set_value(i2c->recovery.scl_gpiod, ibmr & IBMR_SCLS);
+ gpiod_set_value(i2c->recovery.sda_gpiod, ibmr & IBMR_SDAS);
+
+ WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery));
+}
+
+static void i2c_pxa_unprepare_recovery(struct i2c_adapter *adap)
+{
+ struct pxa_i2c *i2c = adap->algo_data;
+ u32 isr;
+
+ /*
+ * The bus should now be free. Clear up the I2C controller before
+ * handing control of the bus back to avoid the bus changing state.
+ */
+ isr = readl(_ISR(i2c));
+ if (isr & (ISR_UB | ISR_IBB)) {
+ dev_dbg(&i2c->adap.dev,
+ "recovery: resetting controller, ISR=0x%08x\n", isr);
+ i2c_pxa_do_reset(i2c);
+ }
+
+ WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default));
+
+ dev_dbg(&i2c->adap.dev, "recovery: IBMR 0x%08x ISR 0x%08x\n",
+ readl(_IBMR(i2c)), readl(_ISR(i2c)));
+
+ i2c_pxa_enable(i2c);
+}
+
+static int i2c_pxa_init_recovery(struct pxa_i2c *i2c)
+{
+ struct i2c_bus_recovery_info *bri = &i2c->recovery;
+ struct device *dev = i2c->adap.dev.parent;
+
+ /*
+ * When slave mode is enabled, we are not the only master on the bus.
+ * Bus recovery can only be performed when we are the master, which
+ * we can't be certain of. Therefore, when slave mode is enabled, do
+ * not configure bus recovery.
+ */
+ if (IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
+ return 0;
+
+ i2c->pinctrl = devm_pinctrl_get(dev);
+ if (IS_ERR(i2c->pinctrl))
+ return PTR_ERR(i2c->pinctrl);
+
+ if (!i2c->pinctrl)
+ return 0;
+
+ i2c->pinctrl_default = pinctrl_lookup_state(i2c->pinctrl,
+ PINCTRL_STATE_DEFAULT);
+ i2c->pinctrl_recovery = pinctrl_lookup_state(i2c->pinctrl, "recovery");
+
+ if (IS_ERR(i2c->pinctrl_default) || IS_ERR(i2c->pinctrl_recovery)) {
+ dev_info(dev, "missing pinmux recovery information: %ld %ld\n",
+ PTR_ERR(i2c->pinctrl_default),
+ PTR_ERR(i2c->pinctrl_recovery));
+ return 0;
+ }
+
+ /*
+ * Claiming GPIOs can influence the pinmux state, and may glitch the
+ * I2C bus. Do this carefully.
+ */
+ bri->scl_gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN);
+ if (bri->scl_gpiod == ERR_PTR(-EPROBE_DEFER))
+ return -EPROBE_DEFER;
+ if (IS_ERR(bri->scl_gpiod)) {
+ dev_info(dev, "missing scl gpio recovery information: %pe\n",
+ bri->scl_gpiod);
+ return 0;
+ }
+
+ /*
+ * We have SCL. Pull SCL low and wait a bit so that SDA glitches
+ * have no effect.
+ */
+ gpiod_direction_output(bri->scl_gpiod, 0);
+ udelay(10);
+ bri->sda_gpiod = devm_gpiod_get(dev, "sda", GPIOD_OUT_HIGH_OPEN_DRAIN);
+
+ /* Wait a bit in case of a SDA glitch, and then release SCL. */
+ udelay(10);
+ gpiod_direction_output(bri->scl_gpiod, 1);
+
+ if (bri->sda_gpiod == ERR_PTR(-EPROBE_DEFER))
+ return -EPROBE_DEFER;
+
+ if (IS_ERR(bri->sda_gpiod)) {
+ dev_info(dev, "missing sda gpio recovery information: %pe\n",
+ bri->sda_gpiod);
+ return 0;
+ }
+
+ bri->prepare_recovery = i2c_pxa_prepare_recovery;
+ bri->unprepare_recovery = i2c_pxa_unprepare_recovery;
+ bri->recover_bus = i2c_generic_scl_recovery;
+
+ i2c->adap.bus_recovery_info = bri;
+
+ /*
+ * Claiming GPIOs can change the pinmux state, which confuses the
+ * pinctrl since pinctrl's idea of the current setting is unaffected
+ * by the pinmux change caused by claiming the GPIO. Work around that
+ * by switching pinctrl to the GPIO state here. We do it this way to
+ * avoid glitching the I2C bus.
+ */
+ pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery);
+
+ return pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default);
+}
+
static int i2c_pxa_probe(struct platform_device *dev)
{
struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev);
@@ -1289,6 +1429,16 @@ static int i2c_pxa_probe(struct platform_device *dev)
if (!i2c)
return -ENOMEM;
+ /* Default adapter num to device id; i2c_pxa_probe_dt can override. */
+ i2c->adap.nr = dev->id;
+ i2c->adap.owner = THIS_MODULE;
+ i2c->adap.retries = 5;
+ i2c->adap.algo_data = i2c;
+ i2c->adap.dev.parent = &dev->dev;
+#ifdef CONFIG_OF
+ i2c->adap.dev.of_node = dev->dev.of_node;
+#endif
+
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
i2c->reg_base = devm_ioremap_resource(&dev->dev, res);
if (IS_ERR(i2c->reg_base))
@@ -1298,8 +1448,9 @@ static int i2c_pxa_probe(struct platform_device *dev)
if (irq < 0)
return irq;
- /* Default adapter num to device id; i2c_pxa_probe_dt can override. */
- i2c->adap.nr = dev->id;
+ ret = i2c_pxa_init_recovery(i2c);
+ if (ret)
+ return ret;
ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
if (ret > 0)
@@ -1307,9 +1458,6 @@ static int i2c_pxa_probe(struct platform_device *dev)
if (ret < 0)
return ret;
- i2c->adap.owner = THIS_MODULE;
- i2c->adap.retries = 5;
-
spin_lock_init(&i2c->lock);
init_waitqueue_head(&i2c->wait);
@@ -1375,12 +1523,6 @@ static int i2c_pxa_probe(struct platform_device *dev)
i2c_pxa_reset(i2c);
- i2c->adap.algo_data = i2c;
- i2c->adap.dev.parent = &dev->dev;
-#ifdef CONFIG_OF
- i2c->adap.dev.of_node = dev->dev.of_node;
-#endif
-
ret = i2c_add_numbered_adapter(&i2c->adap);
if (ret < 0)
goto ereqirq;
--
2.20.1