From fa18902ee1e53ad391a455a01be3ab2ea1c5af5f Mon Sep 17 00:00:00 2001 From: Dom Cobley Date: Fri, 21 May 2021 12:33:38 +0100 Subject: [PATCH] gpio_brcmstb: Allow to build for ARCH_BCM2835 gpio-brcmstb: Report the correct bank width gpio: brcmstb: Use bank address as gpiochip label If the path to the device node is used as gpiochip label then gpio-brcmstb instances with multiple banks end up with duplicated names. Instead, use a combination of the driver name with the physical address of the bank, which is both unique and helpful for devmem debugging. Signed-off-by: Phil Elwell gpio: mmio: Add DIRECT mode for shared access The generic MMIO GPIO library uses shadow registers for efficiency, but this breaks attempts by raspi-gpio to change other GPIOs in the same bank. Add a DIRECT mode that makes fewer assumptions about the existing register contents, but note that genuinely simultaneous accesses are likely to lose updates. Signed-off-by: Phil Elwell gpio: brcmstb: Don't always clear interrupt mask If the GPIO controller is not being used as an interrupt source leave the interrupt mask register alone. On BCM2712 it might be used to generate interrupts to the VPU firmware, and on other devices it doesn't matter since no interrupts will be generated. Signed-off-by: Phil Elwell --- drivers/gpio/Kconfig | 2 +- drivers/gpio/gpio-brcmstb.c | 14 ++-- drivers/gpio/gpio-mmio.c | 124 ++++++++++++++++++++++++++++++++++-- include/linux/gpio/driver.h | 1 + 4 files changed, 131 insertions(+), 10 deletions(-) --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -203,7 +203,7 @@ config GPIO_BCM_VIRT config GPIO_BRCMSTB tristate "BRCMSTB GPIO support" default y if (ARCH_BRCMSTB || BMIPS_GENERIC) - depends on OF_GPIO && (ARCH_BRCMSTB || BMIPS_GENERIC || COMPILE_TEST) + depends on OF_GPIO && (ARCH_BRCMSTB || BMIPS_GENERIC || ARCH_BCM2835 || COMPILE_TEST) select GPIO_GENERIC select IRQ_DOMAIN help --- a/drivers/gpio/gpio-brcmstb.c +++ b/drivers/gpio/gpio-brcmstb.c @@ -640,6 +640,8 @@ static int brcmstb_gpio_probe(struct pla #if defined(CONFIG_MIPS) && defined(__BIG_ENDIAN) flags = BGPIOF_BIG_ENDIAN_BYTE_ORDER; #endif + if (of_property_read_bool(np, "brcm,gpio-direct")) + flags |= BGPIOF_REG_DIRECT; of_property_for_each_u32(np, "brcm,gpio-bank-widths", prop, p, bank_width) { @@ -689,7 +691,9 @@ static int brcmstb_gpio_probe(struct pla } gc->owner = THIS_MODULE; - gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", np); + gc->label = devm_kasprintf(dev, GFP_KERNEL, "gpio-brcmstb@%zx", + (size_t)res->start + + GIO_BANK_OFF(bank->id, 0)); if (!gc->label) { err = -ENOMEM; goto fail; @@ -698,7 +702,7 @@ static int brcmstb_gpio_probe(struct pla gc->of_gpio_n_cells = 2; gc->of_xlate = brcmstb_gpio_of_xlate; /* not all ngpio lines are valid, will use bank width later */ - gc->ngpio = MAX_GPIO_PER_BANK; + gc->ngpio = bank_width; gc->offset = bank->id * MAX_GPIO_PER_BANK; if (priv->parent_irq > 0) gc->to_irq = brcmstb_gpio_to_irq; @@ -707,8 +711,10 @@ static int brcmstb_gpio_probe(struct pla * Mask all interrupts by default, since wakeup interrupts may * be retained from S5 cold boot */ - need_wakeup_event |= !!__brcmstb_gpio_get_active_irqs(bank); - gc->write_reg(reg_base + GIO_MASK(bank->id), 0); + if (priv->parent_irq > 0) { + need_wakeup_event |= !!__brcmstb_gpio_get_active_irqs(bank); + gc->write_reg(reg_base + GIO_MASK(bank->id), 0); + } err = gpiochip_add_data(gc, bank); if (err) { --- a/drivers/gpio/gpio-mmio.c +++ b/drivers/gpio/gpio-mmio.c @@ -232,6 +232,25 @@ static void bgpio_set(struct gpio_chip * raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); } +static void bgpio_set_direct(struct gpio_chip *gc, unsigned int gpio, int val) +{ + unsigned long mask = bgpio_line2mask(gc, gpio); + unsigned long flags; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + gc->bgpio_data = gc->read_reg(gc->reg_dat); + + if (val) + gc->bgpio_data |= mask; + else + gc->bgpio_data &= ~mask; + + gc->write_reg(gc->reg_dat, gc->bgpio_data); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); +} + static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio, int val) { @@ -324,6 +343,27 @@ static void bgpio_set_multiple_with_clea gc->write_reg(gc->reg_clr, clear_mask); } +static void bgpio_set_multiple_direct(struct gpio_chip *gc, + unsigned long *mask, + unsigned long *bits) +{ + unsigned long flags; + unsigned long set_mask, clear_mask; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask); + + gc->bgpio_data = gc->read_reg(gc->reg_dat); + + gc->bgpio_data |= set_mask; + gc->bgpio_data &= ~clear_mask; + + gc->write_reg(gc->reg_dat, gc->bgpio_data); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); +} + static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio) { return 0; @@ -361,6 +401,29 @@ static int bgpio_dir_in(struct gpio_chip return 0; } +static int bgpio_dir_in_direct(struct gpio_chip *gc, unsigned int gpio) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + if (gc->reg_dir_in) + gc->bgpio_dir = ~gc->read_reg(gc->reg_dir_in); + if (gc->reg_dir_out) + gc->bgpio_dir = gc->read_reg(gc->reg_dir_out); + + gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio); + + if (gc->reg_dir_in) + gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); + if (gc->reg_dir_out) + gc->write_reg(gc->reg_dir_out, gc->bgpio_dir); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); + + return 0; +} + static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio) { /* Return 0 if output, 1 if input */ @@ -399,6 +462,28 @@ static void bgpio_dir_out(struct gpio_ch raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); } +static void bgpio_dir_out_direct(struct gpio_chip *gc, unsigned int gpio, + int val) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&gc->bgpio_lock, flags); + + if (gc->reg_dir_in) + gc->bgpio_dir = ~gc->read_reg(gc->reg_dir_in); + if (gc->reg_dir_out) + gc->bgpio_dir = gc->read_reg(gc->reg_dir_out); + + gc->bgpio_dir |= bgpio_line2mask(gc, gpio); + + if (gc->reg_dir_in) + gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); + if (gc->reg_dir_out) + gc->write_reg(gc->reg_dir_out, gc->bgpio_dir); + + raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags); +} + static int bgpio_dir_out_dir_first(struct gpio_chip *gc, unsigned int gpio, int val) { @@ -415,6 +500,22 @@ static int bgpio_dir_out_val_first(struc return 0; } +static int bgpio_dir_out_dir_first_direct(struct gpio_chip *gc, + unsigned int gpio, int val) +{ + bgpio_dir_out_direct(gc, gpio, val); + gc->set(gc, gpio, val); + return 0; +} + +static int bgpio_dir_out_val_first_direct(struct gpio_chip *gc, + unsigned int gpio, int val) +{ + gc->set(gc, gpio, val); + bgpio_dir_out_direct(gc, gpio, val); + return 0; +} + static int bgpio_setup_accessors(struct device *dev, struct gpio_chip *gc, bool byte_be) @@ -508,6 +609,9 @@ static int bgpio_setup_io(struct gpio_ch } else if (flags & BGPIOF_NO_OUTPUT) { gc->set = bgpio_set_none; gc->set_multiple = NULL; + } else if (flags & BGPIOF_REG_DIRECT) { + gc->set = bgpio_set_direct; + gc->set_multiple = bgpio_set_multiple_direct; } else { gc->set = bgpio_set; gc->set_multiple = bgpio_set_multiple; @@ -544,11 +648,21 @@ static int bgpio_setup_direction(struct if (dirout || dirin) { gc->reg_dir_out = dirout; gc->reg_dir_in = dirin; - if (flags & BGPIOF_NO_SET_ON_INPUT) - gc->direction_output = bgpio_dir_out_dir_first; - else - gc->direction_output = bgpio_dir_out_val_first; - gc->direction_input = bgpio_dir_in; + if (flags & BGPIOF_REG_DIRECT) { + if (flags & BGPIOF_NO_SET_ON_INPUT) + gc->direction_output = + bgpio_dir_out_dir_first_direct; + else + gc->direction_output = + bgpio_dir_out_val_first_direct; + gc->direction_input = bgpio_dir_in_direct; + } else { + if (flags & BGPIOF_NO_SET_ON_INPUT) + gc->direction_output = bgpio_dir_out_dir_first; + else + gc->direction_output = bgpio_dir_out_val_first; + gc->direction_input = bgpio_dir_in; + } gc->get_direction = bgpio_get_dir; } else { if (flags & BGPIOF_NO_OUTPUT) --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -690,6 +690,7 @@ int bgpio_init(struct gpio_chip *gc, str #define BGPIOF_READ_OUTPUT_REG_SET BIT(4) /* reg_set stores output value */ #define BGPIOF_NO_OUTPUT BIT(5) /* only input */ #define BGPIOF_NO_SET_ON_INPUT BIT(6) +#define BGPIOF_REG_DIRECT BIT(7) /* ignore shadow registers */ int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hwirq);