From 71479789851bdd9d56cd9e82892b0a3bee0a4c2a Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Thu, 7 Feb 2019 17:28:56 +0100 Subject: gpio: rename gpio_set_drive_single_ended() to gpio_set_config() This commit simply renames gpio_set_drive_single_ended() to gpio_set_config(), as the function is not specific to setting the GPIO drive type, and will be used for other purposes in followup commits. In addition, it moves the function above gpiod_direction_input(), as it will be used from gpiod_direction_input(). Signed-off-by: Thomas Petazzoni Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) (limited to 'drivers/gpio') diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 1651d7f0a303..de595fa31a1a 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2518,6 +2518,14 @@ EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); * rely on gpio_request() having been called beforehand. */ +static int gpio_set_config(struct gpio_chip *gc, unsigned offset, + enum pin_config_param mode) +{ + unsigned long config = { PIN_CONF_PACKED(mode, 0) }; + + return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP; +} + /** * gpiod_direction_input - set the GPIO direction to input * @desc: GPIO to set to input @@ -2571,14 +2579,6 @@ int gpiod_direction_input(struct gpio_desc *desc) } EXPORT_SYMBOL_GPL(gpiod_direction_input); -static int gpio_set_drive_single_ended(struct gpio_chip *gc, unsigned offset, - enum pin_config_param mode) -{ - unsigned long config = { PIN_CONF_PACKED(mode, 0) }; - - return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP; -} - static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) { struct gpio_chip *gc = desc->gdev->chip; @@ -2675,8 +2675,8 @@ int gpiod_direction_output(struct gpio_desc *desc, int value) gc = desc->gdev->chip; if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { /* First see if we can enable open drain in hardware */ - ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), - PIN_CONFIG_DRIVE_OPEN_DRAIN); + ret = gpio_set_config(gc, gpio_chip_hwgpio(desc), + PIN_CONFIG_DRIVE_OPEN_DRAIN); if (!ret) goto set_output_value; /* Emulate open drain by not actively driving the line high */ @@ -2684,16 +2684,16 @@ int gpiod_direction_output(struct gpio_desc *desc, int value) return gpiod_direction_input(desc); } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { - ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), - PIN_CONFIG_DRIVE_OPEN_SOURCE); + ret = gpio_set_config(gc, gpio_chip_hwgpio(desc), + PIN_CONFIG_DRIVE_OPEN_SOURCE); if (!ret) goto set_output_value; /* Emulate open source by not actively driving the line low */ if (!value) return gpiod_direction_input(desc); } else { - gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), - PIN_CONFIG_DRIVE_PUSH_PULL); + gpio_set_config(gc, gpio_chip_hwgpio(desc), + PIN_CONFIG_DRIVE_PUSH_PULL); } set_output_value: -- cgit From 6581eaf0e890756e093e2f44916edb5e7e6558ca Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Thu, 7 Feb 2019 17:28:57 +0100 Subject: gpio: use new gpio_set_config() helper in more places As suggested by Linus Walleij, let's use the new gpio_set_config() helper in gpiod_set_debounce() and gpiod_set_transitory(). Signed-off-by: Thomas Petazzoni Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/gpio') diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index de595fa31a1a..1f239aac43df 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2725,7 +2725,7 @@ int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) } config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce); - return chip->set_config(chip, gpio_chip_hwgpio(desc), config); + return gpio_set_config(chip, gpio_chip_hwgpio(desc), config); } EXPORT_SYMBOL_GPL(gpiod_set_debounce); @@ -2762,7 +2762,7 @@ int gpiod_set_transitory(struct gpio_desc *desc, bool transitory) packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE, !transitory); gpio = gpio_chip_hwgpio(desc); - rc = chip->set_config(chip, gpio, packed); + rc = gpio_set_config(chip, gpio, packed); if (rc == -ENOTSUPP) { dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n", gpio); -- cgit From d449991c4d1d0663b42db7648510a9911de21298 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Thu, 7 Feb 2019 17:28:58 +0100 Subject: gpio: add core support for pull-up/pull-down configuration This commit adds support for configuring the pull-up and pull-down resistors available in some GPIO controllers. While configuring pull-up/pull-down is already possible through the pinctrl subsystem, some GPIO controllers, especially simple ones such as GPIO expanders on I2C, don't have any pinmuxing capability and therefore do not use the pinctrl subsystem. This commit implements the GPIO_PULL_UP and GPIO_PULL_DOWN flags, which can be used from the Device Tree, to enable a pull-up or pull-down resistor on a given GPIO. The flag is simply propagated all the way to the core GPIO subsystem, where it is used to call the gpio_chip ->set_config callback with the appropriate existing PIN_CONFIG_BIAS_* values. Signed-off-by: Thomas Petazzoni Signed-off-by: Linus Walleij --- drivers/gpio/gpiolib-of.c | 5 +++++ drivers/gpio/gpiolib.c | 18 ++++++++++++++++++ drivers/gpio/gpiolib.h | 2 ++ 3 files changed, 25 insertions(+) (limited to 'drivers/gpio') diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index a6e1891217e2..9a8b78477f79 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -345,6 +345,11 @@ struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, if (of_flags & OF_GPIO_TRANSITORY) *flags |= GPIO_TRANSITORY; + if (of_flags & OF_GPIO_PULL_UP) + *flags |= GPIO_PULL_UP; + if (of_flags & OF_GPIO_PULL_DOWN) + *flags |= GPIO_PULL_DOWN; + return desc; } diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 1f239aac43df..22d8b37f5319 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2573,6 +2573,13 @@ int gpiod_direction_input(struct gpio_desc *desc) if (status == 0) clear_bit(FLAG_IS_OUT, &desc->flags); + if (test_bit(FLAG_PULL_UP, &desc->flags)) + gpio_set_config(chip, gpio_chip_hwgpio(desc), + PIN_CONFIG_BIAS_PULL_UP); + else if (test_bit(FLAG_PULL_DOWN, &desc->flags)) + gpio_set_config(chip, gpio_chip_hwgpio(desc), + PIN_CONFIG_BIAS_PULL_DOWN); + trace_gpio_direction(desc_to_gpio(desc), 1, status); return status; @@ -4050,6 +4057,17 @@ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, if (lflags & GPIO_OPEN_SOURCE) set_bit(FLAG_OPEN_SOURCE, &desc->flags); + if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) { + gpiod_err(desc, + "both pull-up and pull-down enabled, invalid configuration\n"); + return -EINVAL; + } + + if (lflags & GPIO_PULL_UP) + set_bit(FLAG_PULL_UP, &desc->flags); + else if (lflags & GPIO_PULL_DOWN) + set_bit(FLAG_PULL_DOWN, &desc->flags); + status = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY)); if (status < 0) return status; diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index bc57f0dc5953..078ab17b96bf 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -219,6 +219,8 @@ struct gpio_desc { #define FLAG_IRQ_IS_ENABLED 10 /* GPIO is connected to an enabled IRQ */ #define FLAG_IS_HOGGED 11 /* GPIO is hogged */ #define FLAG_TRANSITORY 12 /* GPIO may lose value in sleep or reset */ +#define FLAG_PULL_UP 13 /* GPIO has pull up enabled */ +#define FLAG_PULL_DOWN 14 /* GPIO has pull down enabled */ /* Connection label */ const char *label; -- cgit From 15add06841a3b0b4734a72847a73c71fd09ebe52 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Thu, 7 Feb 2019 17:28:59 +0100 Subject: gpio: pca953x: add ->set_config implementation This commit adds a minimal implementation of the ->set_config() hook, with support for the PIN_CONFIG_BIAS_PULL_UP and PIN_CONFIG_BIAS_PULL_DOWN configurations. Signed-off-by: Thomas Petazzoni Signed-off-by: Linus Walleij --- drivers/gpio/gpio-pca953x.c | 66 +++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 64 insertions(+), 2 deletions(-) (limited to 'drivers/gpio') diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index 83617fdc661d..4cace44b179c 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -178,6 +178,8 @@ static int pca953x_bank_shift(struct pca953x_chip *chip) #define PCA957x_BANK_OUTPUT BIT(5) #define PCAL9xxx_BANK_IN_LATCH BIT(8 + 2) +#define PCAL9xxx_BANK_PULL_EN BIT(8 + 3) +#define PCAL9xxx_BANK_PULL_SEL BIT(8 + 4) #define PCAL9xxx_BANK_IRQ_MASK BIT(8 + 5) #define PCAL9xxx_BANK_IRQ_STAT BIT(8 + 6) @@ -199,6 +201,8 @@ static int pca953x_bank_shift(struct pca953x_chip *chip) * - Extended set, above 0x40, often chip specific. * - PCAL6524/PCAL9555A with custom PCAL IRQ handling: * Input latch register 0x40 + 2 * bank_size RW + * Pull-up/pull-down enable reg 0x40 + 3 * bank_size RW + * Pull-up/pull-down select reg 0x40 + 4 * bank_size RW * Interrupt mask register 0x40 + 5 * bank_size RW * Interrupt status register 0x40 + 6 * bank_size R * @@ -247,7 +251,8 @@ static bool pca953x_readable_register(struct device *dev, unsigned int reg) } if (chip->driver_data & PCA_PCAL) { - bank |= PCAL9xxx_BANK_IN_LATCH | PCAL9xxx_BANK_IRQ_MASK | + bank |= PCAL9xxx_BANK_IN_LATCH | PCAL9xxx_BANK_PULL_EN | + PCAL9xxx_BANK_PULL_SEL | PCAL9xxx_BANK_IRQ_MASK | PCAL9xxx_BANK_IRQ_STAT; } @@ -268,7 +273,8 @@ static bool pca953x_writeable_register(struct device *dev, unsigned int reg) } if (chip->driver_data & PCA_PCAL) - bank |= PCAL9xxx_BANK_IN_LATCH | PCAL9xxx_BANK_IRQ_MASK; + bank |= PCAL9xxx_BANK_IN_LATCH | PCAL9xxx_BANK_PULL_EN | + PCAL9xxx_BANK_PULL_SEL | PCAL9xxx_BANK_IRQ_MASK; return pca953x_check_register(chip, reg, bank); } @@ -473,6 +479,61 @@ exit: mutex_unlock(&chip->i2c_lock); } +static int pca953x_gpio_set_pull_up_down(struct pca953x_chip *chip, + unsigned int offset, + unsigned long config) +{ + u8 pull_en_reg = pca953x_recalc_addr(chip, PCAL953X_PULL_EN, offset, + true, false); + u8 pull_sel_reg = pca953x_recalc_addr(chip, PCAL953X_PULL_SEL, offset, + true, false); + u8 bit = BIT(offset % BANK_SZ); + int ret; + + /* + * pull-up/pull-down configuration requires PCAL extended + * registers + */ + if (!(chip->driver_data & PCA_PCAL)) + return -ENOTSUPP; + + mutex_lock(&chip->i2c_lock); + + /* Disable pull-up/pull-down */ + ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, 0); + if (ret) + goto exit; + + /* Configure pull-up/pull-down */ + if (config == PIN_CONFIG_BIAS_PULL_UP) + ret = regmap_write_bits(chip->regmap, pull_sel_reg, bit, bit); + else if (config == PIN_CONFIG_BIAS_PULL_DOWN) + ret = regmap_write_bits(chip->regmap, pull_sel_reg, bit, 0); + if (ret) + goto exit; + + /* Enable pull-up/pull-down */ + ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, bit); + +exit: + mutex_unlock(&chip->i2c_lock); + return ret; +} + +static int pca953x_gpio_set_config(struct gpio_chip *gc, unsigned int offset, + unsigned long config) +{ + struct pca953x_chip *chip = gpiochip_get_data(gc); + + switch (config) { + case PIN_CONFIG_BIAS_PULL_UP: + case PIN_CONFIG_BIAS_PULL_DOWN: + return pca953x_gpio_set_pull_up_down(chip, offset, config); + default: + return -ENOTSUPP; + } +} + static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios) { struct gpio_chip *gc; @@ -485,6 +546,7 @@ static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios) gc->set = pca953x_gpio_set_value; gc->get_direction = pca953x_gpio_get_direction; gc->set_multiple = pca953x_gpio_set_multiple; + gc->set_config = pca953x_gpio_set_config; gc->can_sleep = true; gc->base = chip->gpio_start; -- cgit