mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-27 01:11:14 +00:00
92 lines
3.0 KiB
Diff
92 lines
3.0 KiB
Diff
|
From d1d81802522ade84128a2c66c0d500e372474dca Mon Sep 17 00:00:00 2001
|
||
|
|
From: Torsten Fleischer <torfl6749@gmail.com>
|
||
|
|
Date: Mon, 3 Nov 2014 17:17:55 +0100
|
||
|
|
Subject: [PATCH] spi: spi-gpio: Add dt support for a single device with no
|
||
|
|
chip select
|
||
|
|
|
||
|
|
In order to describe a single slave device that has no chip select line
|
||
|
|
the 'num-chipselects' property has to be <0> and the 'cs-gpios' property
|
||
|
|
doesn't need to be set.
|
||
|
|
|
||
|
|
Signed-off-by: Torsten Fleischer <torfl6749@gmail.com>
|
||
|
|
Signed-off-by: Mark Brown <broonie@kernel.org>
|
||
|
|
---
|
||
|
|
Documentation/devicetree/bindings/spi/spi-gpio.txt | 6 ++++--
|
||
|
|
drivers/spi/spi-gpio.c | 21 +++++++++++++++------
|
||
|
|
2 files changed, 19 insertions(+), 8 deletions(-)
|
||
|
|
|
||
|
|
--- a/Documentation/devicetree/bindings/spi/spi-gpio.txt
|
||
|
|
+++ b/Documentation/devicetree/bindings/spi/spi-gpio.txt
|
||
|
|
@@ -8,8 +8,10 @@ Required properties:
|
||
|
|
- gpio-sck: GPIO spec for the SCK line to use
|
||
|
|
- gpio-miso: GPIO spec for the MISO line to use
|
||
|
|
- gpio-mosi: GPIO spec for the MOSI line to use
|
||
|
|
- - cs-gpios: GPIOs to use for chipselect lines
|
||
|
|
- - num-chipselects: number of chipselect lines
|
||
|
|
+ - cs-gpios: GPIOs to use for chipselect lines.
|
||
|
|
+ Not needed if num-chipselects = <0>.
|
||
|
|
+ - num-chipselects: Number of chipselect lines. Should be <0> if a single device
|
||
|
|
+ with no chip select is connected.
|
||
|
|
|
||
|
|
Example:
|
||
|
|
|
||
|
|
--- a/drivers/spi/spi-gpio.c
|
||
|
|
+++ b/drivers/spi/spi-gpio.c
|
||
|
|
@@ -424,6 +424,7 @@ static int spi_gpio_probe(struct platfor
|
||
|
|
struct spi_gpio_platform_data *pdata;
|
||
|
|
u16 master_flags = 0;
|
||
|
|
bool use_of = 0;
|
||
|
|
+ int num_devices;
|
||
|
|
|
||
|
|
status = spi_gpio_probe_dt(pdev);
|
||
|
|
if (status < 0)
|
||
|
|
@@ -433,16 +434,21 @@ static int spi_gpio_probe(struct platfor
|
||
|
|
|
||
|
|
pdata = dev_get_platdata(&pdev->dev);
|
||
|
|
#ifdef GENERIC_BITBANG
|
||
|
|
- if (!pdata || !pdata->num_chipselect)
|
||
|
|
+ if (!pdata || (!use_of && !pdata->num_chipselect))
|
||
|
|
return -ENODEV;
|
||
|
|
#endif
|
||
|
|
|
||
|
|
+ if (use_of && !SPI_N_CHIPSEL)
|
||
|
|
+ num_devices = 1;
|
||
|
|
+ else
|
||
|
|
+ num_devices = SPI_N_CHIPSEL;
|
||
|
|
+
|
||
|
|
status = spi_gpio_request(pdata, dev_name(&pdev->dev), &master_flags);
|
||
|
|
if (status < 0)
|
||
|
|
return status;
|
||
|
|
|
||
|
|
master = spi_alloc_master(&pdev->dev, sizeof(*spi_gpio) +
|
||
|
|
- (sizeof(int) * SPI_N_CHIPSEL));
|
||
|
|
+ (sizeof(int) * num_devices));
|
||
|
|
if (!master) {
|
||
|
|
status = -ENOMEM;
|
||
|
|
goto gpio_free;
|
||
|
|
@@ -457,7 +463,7 @@ static int spi_gpio_probe(struct platfor
|
||
|
|
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
|
||
|
|
master->flags = master_flags;
|
||
|
|
master->bus_num = pdev->id;
|
||
|
|
- master->num_chipselect = SPI_N_CHIPSEL;
|
||
|
|
+ master->num_chipselect = num_devices;
|
||
|
|
master->setup = spi_gpio_setup;
|
||
|
|
master->cleanup = spi_gpio_cleanup;
|
||
|
|
#ifdef CONFIG_OF
|
||
|
|
@@ -472,9 +478,12 @@ static int spi_gpio_probe(struct platfor
|
||
|
|
* property of the node.
|
||
|
|
*/
|
||
|
|
|
||
|
|
- for (i = 0; i < SPI_N_CHIPSEL; i++)
|
||
|
|
- spi_gpio->cs_gpios[i] =
|
||
|
|
- of_get_named_gpio(np, "cs-gpios", i);
|
||
|
|
+ if (!SPI_N_CHIPSEL)
|
||
|
|
+ spi_gpio->cs_gpios[0] = SPI_GPIO_NO_CHIPSELECT;
|
||
|
|
+ else
|
||
|
|
+ for (i = 0; i < SPI_N_CHIPSEL; i++)
|
||
|
|
+ spi_gpio->cs_gpios[i] =
|
||
|
|
+ of_get_named_gpio(np, "cs-gpios", i);
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|