| Message ID | 1552082608-42603-3-git-send-email-justinpopo6@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | iio: adc: ads7950: add gpio support | expand |
On Fri, 8 Mar 2019 14:03:28 -0800 justinpopo6@gmail.com wrote: > From: Justin Chen <justinpopo6@gmail.com> > > The ADS79XX has GPIO pins that can be used. Add support for the GPIO > pins using the GPIO chip framework. > > Signed-off-by: Justin Chen <justinpopo6@gmail.com> > Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Applied to the togreg branch of iio.git and pushed out as testing for the autobuilders to play with it. Thanks, Jonathan > --- > drivers/iio/adc/ti-ads7950.c | 200 +++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 194 insertions(+), 6 deletions(-) > > diff --git a/drivers/iio/adc/ti-ads7950.c b/drivers/iio/adc/ti-ads7950.c > index 1e47bef..2e66e4d 100644 > --- a/drivers/iio/adc/ti-ads7950.c > +++ b/drivers/iio/adc/ti-ads7950.c > @@ -17,6 +17,7 @@ > #include <linux/bitops.h> > #include <linux/device.h> > #include <linux/err.h> > +#include <linux/gpio/driver.h> > #include <linux/interrupt.h> > #include <linux/kernel.h> > #include <linux/module.h> > @@ -36,12 +37,15 @@ > */ > #define TI_ADS7950_VA_MV_ACPI_DEFAULT 5000 > > +#define TI_ADS7950_CR_GPIO BIT(14) > #define TI_ADS7950_CR_MANUAL BIT(12) > #define TI_ADS7950_CR_WRITE BIT(11) > #define TI_ADS7950_CR_CHAN(ch) ((ch) << 7) > #define TI_ADS7950_CR_RANGE_5V BIT(6) > +#define TI_ADS7950_CR_GPIO_DATA BIT(4) > > #define TI_ADS7950_MAX_CHAN 16 > +#define TI_ADS7950_NUM_GPIOS 4 > > #define TI_ADS7950_TIMESTAMP_SIZE (sizeof(int64_t) / sizeof(__be16)) > > @@ -49,6 +53,16 @@ > #define TI_ADS7950_EXTRACT(val, dec, bits) \ > (((val) >> (dec)) & ((1 << (bits)) - 1)) > > +#define TI_ADS7950_MAN_CMD(cmd) (TI_ADS7950_CR_MANUAL | (cmd)) > +#define TI_ADS7950_GPIO_CMD(cmd) (TI_ADS7950_CR_GPIO | (cmd)) > + > +/* Manual mode configuration */ > +#define TI_ADS7950_MAN_CMD_SETTINGS(st) \ > + (TI_ADS7950_MAN_CMD(TI_ADS7950_CR_WRITE | st->cmd_settings_bitmask)) > +/* GPIO mode configuration */ > +#define TI_ADS7950_GPIO_CMD_SETTINGS(st) \ > + (TI_ADS7950_GPIO_CMD(st->gpio_cmd_settings_bitmask)) > + > struct ti_ads7950_state { > struct spi_device *spi; > struct spi_transfer ring_xfer; > @@ -58,11 +72,34 @@ struct ti_ads7950_state { > > /* Lock to protect the spi xfer buffers */ > struct mutex slock; > + struct gpio_chip chip; > > struct regulator *reg; > unsigned int vref_mv; > > - unsigned int settings; > + /* > + * Bitmask of lower 7 bits used for configuration > + * These bits only can be written when TI_ADS7950_CR_WRITE > + * is set, otherwise it retains its original state. > + * [0-3] GPIO signal > + * [4] Set following frame to return GPIO signal values > + * [5] Powers down device > + * [6] Sets Vref range1(2.5v) or range2(5v) > + * > + * Bits present on Manual/Auto1/Auto2 commands > + */ > + unsigned int cmd_settings_bitmask; > + > + /* > + * Bitmask of GPIO command > + * [0-3] GPIO direction > + * [4-6] Different GPIO alarm mode configurations > + * [7] GPIO 2 as device range input > + * [8] GPIO 3 as device power down input > + * [9] Reset all registers > + * [10-11] N/A > + */ > + unsigned int gpio_cmd_settings_bitmask; > > /* > * DMA (thus cache coherency maintenance) requires the > @@ -251,7 +288,7 @@ static int ti_ads7950_update_scan_mode(struct iio_dev *indio_dev, > > len = 0; > for_each_set_bit(i, active_scan_mask, indio_dev->num_channels) { > - cmd = TI_ADS7950_CR_WRITE | TI_ADS7950_CR_CHAN(i) | st->settings; > + cmd = TI_ADS7950_MAN_CMD(TI_ADS7950_CR_CHAN(i)); > st->tx_buf[len++] = cmd; > } > > @@ -292,8 +329,7 @@ static int ti_ads7950_scan_direct(struct iio_dev *indio_dev, unsigned int ch) > int ret, cmd; > > mutex_lock(&st->slock); > - > - cmd = TI_ADS7950_CR_WRITE | TI_ADS7950_CR_CHAN(ch) | st->settings; > + cmd = TI_ADS7950_MAN_CMD(TI_ADS7950_CR_CHAN(ch)); > st->single_tx = cmd; > > ret = spi_sync(st->spi, &st->scan_single_msg); > @@ -322,7 +358,7 @@ static int ti_ads7950_get_range(struct ti_ads7950_state *st) > vref /= 1000; > } > > - if (st->settings & TI_ADS7950_CR_RANGE_5V) > + if (st->cmd_settings_bitmask & TI_ADS7950_CR_RANGE_5V) > vref *= 2; > > return vref; > @@ -367,6 +403,132 @@ static const struct iio_info ti_ads7950_info = { > .update_scan_mode = ti_ads7950_update_scan_mode, > }; > > +static void ti_ads7950_set(struct gpio_chip *chip, unsigned int offset, > + int value) > +{ > + struct ti_ads7950_state *st = gpiochip_get_data(chip); > + > + mutex_lock(&st->slock); > + > + if (value) > + st->cmd_settings_bitmask |= BIT(offset); > + else > + st->cmd_settings_bitmask &= ~BIT(offset); > + > + st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st); > + spi_sync(st->spi, &st->scan_single_msg); > + > + mutex_unlock(&st->slock); > +} > + > +static int ti_ads7950_get(struct gpio_chip *chip, unsigned int offset) > +{ > + struct ti_ads7950_state *st = gpiochip_get_data(chip); > + int ret; > + > + mutex_lock(&st->slock); > + > + /* If set as output, return the output */ > + if (st->gpio_cmd_settings_bitmask & BIT(offset)) { > + ret = st->cmd_settings_bitmask & BIT(offset); > + goto out; > + } > + > + /* GPIO data bit sets SDO bits 12-15 to GPIO input */ > + st->cmd_settings_bitmask |= TI_ADS7950_CR_GPIO_DATA; > + st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st); > + ret = spi_sync(st->spi, &st->scan_single_msg); > + if (ret) > + goto out; > + > + ret = ((st->single_rx >> 12) & BIT(offset)) ? 1 : 0; > + > + /* Revert back to original settings */ > + st->cmd_settings_bitmask &= ~TI_ADS7950_CR_GPIO_DATA; > + st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st); > + ret = spi_sync(st->spi, &st->scan_single_msg); > + if (ret) > + goto out; > + > +out: > + mutex_unlock(&st->slock); > + > + return ret; > +} > + > +static int ti_ads7950_get_direction(struct gpio_chip *chip, > + unsigned int offset) > +{ > + struct ti_ads7950_state *st = gpiochip_get_data(chip); > + > + /* Bitmask is inverted from GPIO framework 0=input/1=output */ > + return !(st->gpio_cmd_settings_bitmask & BIT(offset)); > +} > + > +static int _ti_ads7950_set_direction(struct gpio_chip *chip, int offset, > + int input) > +{ > + struct ti_ads7950_state *st = gpiochip_get_data(chip); > + int ret = 0; > + > + mutex_lock(&st->slock); > + > + /* Only change direction if needed */ > + if (input && (st->gpio_cmd_settings_bitmask & BIT(offset))) > + st->gpio_cmd_settings_bitmask &= ~BIT(offset); > + else if (!input && !(st->gpio_cmd_settings_bitmask & BIT(offset))) > + st->gpio_cmd_settings_bitmask |= BIT(offset); > + else > + goto out; > + > + st->single_tx = TI_ADS7950_GPIO_CMD_SETTINGS(st); > + ret = spi_sync(st->spi, &st->scan_single_msg); > + > +out: > + mutex_unlock(&st->slock); > + > + return ret; > +} > + > +static int ti_ads7950_direction_input(struct gpio_chip *chip, > + unsigned int offset) > +{ > + return _ti_ads7950_set_direction(chip, offset, 1); > +} > + > +static int ti_ads7950_direction_output(struct gpio_chip *chip, > + unsigned int offset, int value) > +{ > + ti_ads7950_set(chip, offset, value); > + > + return _ti_ads7950_set_direction(chip, offset, 0); > +} > + > +static int ti_ads7950_init_hw(struct ti_ads7950_state *st) > +{ > + int ret = 0; > + > + mutex_lock(&st->slock); > + > + /* Settings for Manual/Auto1/Auto2 commands */ > + /* Default to 5v ref */ > + st->cmd_settings_bitmask = TI_ADS7950_CR_RANGE_5V; > + st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st); > + ret = spi_sync(st->spi, &st->scan_single_msg); > + if (ret) > + goto out; > + > + /* Settings for GPIO command */ > + st->gpio_cmd_settings_bitmask = 0x0; > + st->single_tx = TI_ADS7950_GPIO_CMD_SETTINGS(st); > + ret = spi_sync(st->spi, &st->scan_single_msg); > + > +out: > + mutex_unlock(&st->slock); > + > + return ret; > +} > + > static int ti_ads7950_probe(struct spi_device *spi) > { > struct ti_ads7950_state *st; > @@ -391,7 +553,6 @@ static int ti_ads7950_probe(struct spi_device *spi) > spi_set_drvdata(spi, indio_dev); > > st->spi = spi; > - st->settings = TI_ADS7950_CR_MANUAL | TI_ADS7950_CR_RANGE_5V; > > info = &ti_ads7950_chip_info[spi_get_device_id(spi)->driver_data]; > > @@ -459,14 +620,40 @@ static int ti_ads7950_probe(struct spi_device *spi) > goto error_disable_reg; > } > > + ret = ti_ads7950_init_hw(st); > + if (ret) { > + dev_err(&spi->dev, "Failed to init adc chip\n"); > + goto error_cleanup_ring; > + } > + > ret = iio_device_register(indio_dev); > if (ret) { > dev_err(&spi->dev, "Failed to register iio device\n"); > goto error_cleanup_ring; > } > > + /* Add GPIO chip */ > + st->chip.label = dev_name(&st->spi->dev); > + st->chip.parent = &st->spi->dev; > + st->chip.owner = THIS_MODULE; > + st->chip.base = -1; > + st->chip.ngpio = TI_ADS7950_NUM_GPIOS; > + st->chip.get_direction = ti_ads7950_get_direction; > + st->chip.direction_input = ti_ads7950_direction_input; > + st->chip.direction_output = ti_ads7950_direction_output; > + st->chip.get = ti_ads7950_get; > + st->chip.set = ti_ads7950_set; > + > + ret = gpiochip_add_data(&st->chip, st); > + if (ret) { > + dev_err(&spi->dev, "Failed to init GPIOs\n"); > + goto error_iio_device; > + } > + > return 0; > > +error_iio_device: > + iio_device_unregister(indio_dev); > error_cleanup_ring: > iio_triggered_buffer_cleanup(indio_dev); > error_disable_reg: > @@ -482,6 +669,7 @@ static int ti_ads7950_remove(struct spi_device *spi) > struct iio_dev *indio_dev = spi_get_drvdata(spi); > struct ti_ads7950_state *st = iio_priv(indio_dev); > > + gpiochip_remove(&st->chip); > iio_device_unregister(indio_dev); > iio_triggered_buffer_cleanup(indio_dev); > regulator_disable(st->reg);
diff --git a/drivers/iio/adc/ti-ads7950.c b/drivers/iio/adc/ti-ads7950.c index 1e47bef..2e66e4d 100644 --- a/drivers/iio/adc/ti-ads7950.c +++ b/drivers/iio/adc/ti-ads7950.c @@ -17,6 +17,7 @@ #include <linux/bitops.h> #include <linux/device.h> #include <linux/err.h> +#include <linux/gpio/driver.h> #include <linux/interrupt.h> #include <linux/kernel.h> #include <linux/module.h> @@ -36,12 +37,15 @@ */ #define TI_ADS7950_VA_MV_ACPI_DEFAULT 5000 +#define TI_ADS7950_CR_GPIO BIT(14) #define TI_ADS7950_CR_MANUAL BIT(12) #define TI_ADS7950_CR_WRITE BIT(11) #define TI_ADS7950_CR_CHAN(ch) ((ch) << 7) #define TI_ADS7950_CR_RANGE_5V BIT(6) +#define TI_ADS7950_CR_GPIO_DATA BIT(4) #define TI_ADS7950_MAX_CHAN 16 +#define TI_ADS7950_NUM_GPIOS 4 #define TI_ADS7950_TIMESTAMP_SIZE (sizeof(int64_t) / sizeof(__be16)) @@ -49,6 +53,16 @@ #define TI_ADS7950_EXTRACT(val, dec, bits) \ (((val) >> (dec)) & ((1 << (bits)) - 1)) +#define TI_ADS7950_MAN_CMD(cmd) (TI_ADS7950_CR_MANUAL | (cmd)) +#define TI_ADS7950_GPIO_CMD(cmd) (TI_ADS7950_CR_GPIO | (cmd)) + +/* Manual mode configuration */ +#define TI_ADS7950_MAN_CMD_SETTINGS(st) \ + (TI_ADS7950_MAN_CMD(TI_ADS7950_CR_WRITE | st->cmd_settings_bitmask)) +/* GPIO mode configuration */ +#define TI_ADS7950_GPIO_CMD_SETTINGS(st) \ + (TI_ADS7950_GPIO_CMD(st->gpio_cmd_settings_bitmask)) + struct ti_ads7950_state { struct spi_device *spi; struct spi_transfer ring_xfer; @@ -58,11 +72,34 @@ struct ti_ads7950_state { /* Lock to protect the spi xfer buffers */ struct mutex slock; + struct gpio_chip chip; struct regulator *reg; unsigned int vref_mv; - unsigned int settings; + /* + * Bitmask of lower 7 bits used for configuration + * These bits only can be written when TI_ADS7950_CR_WRITE + * is set, otherwise it retains its original state. + * [0-3] GPIO signal + * [4] Set following frame to return GPIO signal values + * [5] Powers down device + * [6] Sets Vref range1(2.5v) or range2(5v) + * + * Bits present on Manual/Auto1/Auto2 commands + */ + unsigned int cmd_settings_bitmask; + + /* + * Bitmask of GPIO command + * [0-3] GPIO direction + * [4-6] Different GPIO alarm mode configurations + * [7] GPIO 2 as device range input + * [8] GPIO 3 as device power down input + * [9] Reset all registers + * [10-11] N/A + */ + unsigned int gpio_cmd_settings_bitmask; /* * DMA (thus cache coherency maintenance) requires the @@ -251,7 +288,7 @@ static int ti_ads7950_update_scan_mode(struct iio_dev *indio_dev, len = 0; for_each_set_bit(i, active_scan_mask, indio_dev->num_channels) { - cmd = TI_ADS7950_CR_WRITE | TI_ADS7950_CR_CHAN(i) | st->settings; + cmd = TI_ADS7950_MAN_CMD(TI_ADS7950_CR_CHAN(i)); st->tx_buf[len++] = cmd; } @@ -292,8 +329,7 @@ static int ti_ads7950_scan_direct(struct iio_dev *indio_dev, unsigned int ch) int ret, cmd; mutex_lock(&st->slock); - - cmd = TI_ADS7950_CR_WRITE | TI_ADS7950_CR_CHAN(ch) | st->settings; + cmd = TI_ADS7950_MAN_CMD(TI_ADS7950_CR_CHAN(ch)); st->single_tx = cmd; ret = spi_sync(st->spi, &st->scan_single_msg); @@ -322,7 +358,7 @@ static int ti_ads7950_get_range(struct ti_ads7950_state *st) vref /= 1000; } - if (st->settings & TI_ADS7950_CR_RANGE_5V) + if (st->cmd_settings_bitmask & TI_ADS7950_CR_RANGE_5V) vref *= 2; return vref; @@ -367,6 +403,132 @@ static const struct iio_info ti_ads7950_info = { .update_scan_mode = ti_ads7950_update_scan_mode, }; +static void ti_ads7950_set(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct ti_ads7950_state *st = gpiochip_get_data(chip); + + mutex_lock(&st->slock); + + if (value) + st->cmd_settings_bitmask |= BIT(offset); + else + st->cmd_settings_bitmask &= ~BIT(offset); + + st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st); + spi_sync(st->spi, &st->scan_single_msg); + + mutex_unlock(&st->slock); +} + +static int ti_ads7950_get(struct gpio_chip *chip, unsigned int offset) +{ + struct ti_ads7950_state *st = gpiochip_get_data(chip); + int ret; + + mutex_lock(&st->slock); + + /* If set as output, return the output */ + if (st->gpio_cmd_settings_bitmask & BIT(offset)) { + ret = st->cmd_settings_bitmask & BIT(offset); + goto out; + } + + /* GPIO data bit sets SDO bits 12-15 to GPIO input */ + st->cmd_settings_bitmask |= TI_ADS7950_CR_GPIO_DATA; + st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st); + ret = spi_sync(st->spi, &st->scan_single_msg); + if (ret) + goto out; + + ret = ((st->single_rx >> 12) & BIT(offset)) ? 1 : 0; + + /* Revert back to original settings */ + st->cmd_settings_bitmask &= ~TI_ADS7950_CR_GPIO_DATA; + st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st); + ret = spi_sync(st->spi, &st->scan_single_msg); + if (ret) + goto out; + +out: + mutex_unlock(&st->slock); + + return ret; +} + +static int ti_ads7950_get_direction(struct gpio_chip *chip, + unsigned int offset) +{ + struct ti_ads7950_state *st = gpiochip_get_data(chip); + + /* Bitmask is inverted from GPIO framework 0=input/1=output */ + return !(st->gpio_cmd_settings_bitmask & BIT(offset)); +} + +static int _ti_ads7950_set_direction(struct gpio_chip *chip, int offset, + int input) +{ + struct ti_ads7950_state *st = gpiochip_get_data(chip); + int ret = 0; + + mutex_lock(&st->slock); + + /* Only change direction if needed */ + if (input && (st->gpio_cmd_settings_bitmask & BIT(offset))) + st->gpio_cmd_settings_bitmask &= ~BIT(offset); + else if (!input && !(st->gpio_cmd_settings_bitmask & BIT(offset))) + st->gpio_cmd_settings_bitmask |= BIT(offset); + else + goto out; + + st->single_tx = TI_ADS7950_GPIO_CMD_SETTINGS(st); + ret = spi_sync(st->spi, &st->scan_single_msg); + +out: + mutex_unlock(&st->slock); + + return ret; +} + +static int ti_ads7950_direction_input(struct gpio_chip *chip, + unsigned int offset) +{ + return _ti_ads7950_set_direction(chip, offset, 1); +} + +static int ti_ads7950_direction_output(struct gpio_chip *chip, + unsigned int offset, int value) +{ + ti_ads7950_set(chip, offset, value); + + return _ti_ads7950_set_direction(chip, offset, 0); +} + +static int ti_ads7950_init_hw(struct ti_ads7950_state *st) +{ + int ret = 0; + + mutex_lock(&st->slock); + + /* Settings for Manual/Auto1/Auto2 commands */ + /* Default to 5v ref */ + st->cmd_settings_bitmask = TI_ADS7950_CR_RANGE_5V; + st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st); + ret = spi_sync(st->spi, &st->scan_single_msg); + if (ret) + goto out; + + /* Settings for GPIO command */ + st->gpio_cmd_settings_bitmask = 0x0; + st->single_tx = TI_ADS7950_GPIO_CMD_SETTINGS(st); + ret = spi_sync(st->spi, &st->scan_single_msg); + +out: + mutex_unlock(&st->slock); + + return ret; +} + static int ti_ads7950_probe(struct spi_device *spi) { struct ti_ads7950_state *st; @@ -391,7 +553,6 @@ static int ti_ads7950_probe(struct spi_device *spi) spi_set_drvdata(spi, indio_dev); st->spi = spi; - st->settings = TI_ADS7950_CR_MANUAL | TI_ADS7950_CR_RANGE_5V; info = &ti_ads7950_chip_info[spi_get_device_id(spi)->driver_data]; @@ -459,14 +620,40 @@ static int ti_ads7950_probe(struct spi_device *spi) goto error_disable_reg; } + ret = ti_ads7950_init_hw(st); + if (ret) { + dev_err(&spi->dev, "Failed to init adc chip\n"); + goto error_cleanup_ring; + } + ret = iio_device_register(indio_dev); if (ret) { dev_err(&spi->dev, "Failed to register iio device\n"); goto error_cleanup_ring; } + /* Add GPIO chip */ + st->chip.label = dev_name(&st->spi->dev); + st->chip.parent = &st->spi->dev; + st->chip.owner = THIS_MODULE; + st->chip.base = -1; + st->chip.ngpio = TI_ADS7950_NUM_GPIOS; + st->chip.get_direction = ti_ads7950_get_direction; + st->chip.direction_input = ti_ads7950_direction_input; + st->chip.direction_output = ti_ads7950_direction_output; + st->chip.get = ti_ads7950_get; + st->chip.set = ti_ads7950_set; + + ret = gpiochip_add_data(&st->chip, st); + if (ret) { + dev_err(&spi->dev, "Failed to init GPIOs\n"); + goto error_iio_device; + } + return 0; +error_iio_device: + iio_device_unregister(indio_dev); error_cleanup_ring: iio_triggered_buffer_cleanup(indio_dev); error_disable_reg: @@ -482,6 +669,7 @@ static int ti_ads7950_remove(struct spi_device *spi) struct iio_dev *indio_dev = spi_get_drvdata(spi); struct ti_ads7950_state *st = iio_priv(indio_dev); + gpiochip_remove(&st->chip); iio_device_unregister(indio_dev); iio_triggered_buffer_cleanup(indio_dev); regulator_disable(st->reg);