From 168115f989311867b48292f4f056eb2f96cef67b Mon Sep 17 00:00:00 2001 From: David Lechner Date: Fri, 29 Sep 2023 12:23:18 -0500 Subject: staging: iio: resolver: ad2s1210: rework gpios - Remove "adi," prefix from gpio names. - Sample gpio is now expected to be active low. - Convert A0 and A1 gpios to "mode-gpios" gpio array. - Convert RES0 and RES1 gpios to "resolution-gpios" gpio array. - Remove extraneous lookup tables. - Remove unused mode field from state struct. - Swap argument order of ad2s1210_set_mode() while we are touching this. Signed-off-by: David Lechner Link: https://lore.kernel.org/r/20230929-ad2s1210-mainline-v3-13-fa4364281745@baylibre.com Signed-off-by: Jonathan Cameron --- drivers/staging/iio/resolver/ad2s1210.c | 164 +++++++++++++++++--------------- 1 file changed, 85 insertions(+), 79 deletions(-) (limited to 'drivers/staging/iio/resolver/ad2s1210.c') diff --git a/drivers/staging/iio/resolver/ad2s1210.c b/drivers/staging/iio/resolver/ad2s1210.c index 2b9377447f6a..5744f1673cba 100644 --- a/drivers/staging/iio/resolver/ad2s1210.c +++ b/drivers/staging/iio/resolver/ad2s1210.c @@ -58,39 +58,21 @@ #define AD2S1210_DEF_EXCIT 10000 enum ad2s1210_mode { - MOD_POS = 0, - MOD_VEL, - MOD_CONFIG, - MOD_RESERVED, + MOD_POS = 0b00, + MOD_VEL = 0b01, + MOD_RESERVED = 0b10, + MOD_CONFIG = 0b11, }; -enum ad2s1210_gpios { - AD2S1210_SAMPLE, - AD2S1210_A0, - AD2S1210_A1, - AD2S1210_RES0, - AD2S1210_RES1, -}; - -struct ad2s1210_gpio { - const char *name; - unsigned long flags; -}; - -static const struct ad2s1210_gpio gpios[] = { - [AD2S1210_SAMPLE] = { .name = "adi,sample", .flags = GPIOD_OUT_LOW }, - [AD2S1210_A0] = { .name = "adi,a0", .flags = GPIOD_OUT_LOW }, - [AD2S1210_A1] = { .name = "adi,a1", .flags = GPIOD_OUT_LOW }, - [AD2S1210_RES0] = { .name = "adi,res0", .flags = GPIOD_OUT_LOW }, - [AD2S1210_RES1] = { .name = "adi,res1", .flags = GPIOD_OUT_LOW }, -}; - -static const unsigned int ad2s1210_resolution_value[] = { 10, 12, 14, 16 }; - struct ad2s1210_state { struct mutex lock; struct spi_device *sdev; - struct gpio_desc *gpios[5]; + /** GPIO pin connected to SAMPLE line. */ + struct gpio_desc *sample_gpio; + /** GPIO pins connected to A0 and A1 lines. */ + struct gpio_descs *mode_gpios; + /** GPIO pins connected to RES0 and RES1 lines. */ + struct gpio_descs *resolution_gpios; /** Used to access config registers. */ struct regmap *regmap; /** The external oscillator frequency in Hz. */ @@ -98,7 +80,6 @@ struct ad2s1210_state { unsigned int fexcit; bool hysteresis; u8 resolution; - enum ad2s1210_mode mode; /** For reading raw sample value via SPI. */ __be16 sample __aligned(IIO_DMA_MINALIGN); /** SPI transmit buffer. */ @@ -107,18 +88,15 @@ struct ad2s1210_state { u8 tx[2]; }; -static const int ad2s1210_mode_vals[4][2] = { - [MOD_POS] = { 0, 0 }, - [MOD_VEL] = { 0, 1 }, - [MOD_CONFIG] = { 1, 1 }, -}; - -static inline void ad2s1210_set_mode(enum ad2s1210_mode mode, - struct ad2s1210_state *st) +static int ad2s1210_set_mode(struct ad2s1210_state *st, enum ad2s1210_mode mode) { - gpiod_set_value(st->gpios[AD2S1210_A0], ad2s1210_mode_vals[mode][0]); - gpiod_set_value(st->gpios[AD2S1210_A1], ad2s1210_mode_vals[mode][1]); - st->mode = mode; + struct gpio_descs *gpios = st->mode_gpios; + DECLARE_BITMAP(bitmap, 2); + + bitmap[0] = mode; + + return gpiod_set_array_value(gpios->ndescs, gpios->desc, gpios->info, + bitmap); } /* @@ -143,6 +121,7 @@ static int ad2s1210_regmap_reg_write(void *context, unsigned int reg, .tx_buf = &st->tx[1], }, }; + int ret; /* values can only be 7 bits, the MSB indicates an address */ if (val & ~0x7F) @@ -151,7 +130,9 @@ static int ad2s1210_regmap_reg_write(void *context, unsigned int reg, st->tx[0] = reg; st->tx[1] = val; - ad2s1210_set_mode(MOD_CONFIG, st); + ret = ad2s1210_set_mode(st, MOD_CONFIG); + if (ret < 0) + return ret; return spi_sync_transfer(st->sdev, xfers, ARRAY_SIZE(xfers)); } @@ -180,7 +161,10 @@ static int ad2s1210_regmap_reg_read(void *context, unsigned int reg, }; int ret; - ad2s1210_set_mode(MOD_CONFIG, st); + ret = ad2s1210_set_mode(st, MOD_CONFIG); + if (ret < 0) + return ret; + st->tx[0] = reg; /* * Must be valid register address here otherwise this could write data. @@ -219,16 +203,16 @@ int ad2s1210_update_frequency_control_word(struct ad2s1210_state *st) return regmap_write(st->regmap, AD2S1210_REG_EXCIT_FREQ, fcw); } -static const int ad2s1210_res_pins[4][2] = { - { 0, 0 }, {0, 1}, {1, 0}, {1, 1} -}; - -static inline void ad2s1210_set_resolution_pin(struct ad2s1210_state *st) +static int ad2s1210_set_resolution_gpios(struct ad2s1210_state *st, + u8 resolution) { - gpiod_set_value(st->gpios[AD2S1210_RES0], - ad2s1210_res_pins[(st->resolution - 10) / 2][0]); - gpiod_set_value(st->gpios[AD2S1210_RES1], - ad2s1210_res_pins[(st->resolution - 10) / 2][1]); + struct gpio_descs *gpios = st->resolution_gpios; + DECLARE_BITMAP(bitmap, 2); + + bitmap[0] = (resolution - 10) >> 1; + + return gpiod_set_array_value(gpios->ndescs, gpios->desc, gpios->info, + bitmap); } static inline int ad2s1210_soft_reset(struct ad2s1210_state *st) @@ -305,10 +289,13 @@ static ssize_t ad2s1210_store_resolution(struct device *dev, if (ret < 0) goto error_ret; - st->resolution = - ad2s1210_resolution_value[data & AD2S1210_SET_RES]; - ad2s1210_set_resolution_pin(st); + ret = ad2s1210_set_resolution_gpios(st, udata); + if (ret < 0) + goto error_ret; + + st->resolution = udata; ret = len; + error_ret: mutex_unlock(&st->lock); return ret; @@ -339,15 +326,19 @@ static ssize_t ad2s1210_clear_fault(struct device *dev, int ret; mutex_lock(&st->lock); - gpiod_set_value(st->gpios[AD2S1210_SAMPLE], 0); + + gpiod_set_value(st->sample_gpio, 1); /* delay (2 * tck + 20) nano seconds */ udelay(1); - gpiod_set_value(st->gpios[AD2S1210_SAMPLE], 1); + gpiod_set_value(st->sample_gpio, 0); + ret = regmap_read(st->regmap, AD2S1210_REG_FAULT, &value); if (ret < 0) goto error_ret; - gpiod_set_value(st->gpios[AD2S1210_SAMPLE], 0); - gpiod_set_value(st->gpios[AD2S1210_SAMPLE], 1); + + gpiod_set_value(st->sample_gpio, 1); + gpiod_set_value(st->sample_gpio, 0); + error_ret: mutex_unlock(&st->lock); @@ -393,19 +384,19 @@ static int ad2s1210_single_conversion(struct ad2s1210_state *st, struct iio_chan_spec const *chan, int *val) { - int ret = 0; + int ret; mutex_lock(&st->lock); - gpiod_set_value(st->gpios[AD2S1210_SAMPLE], 0); + gpiod_set_value(st->sample_gpio, 1); /* delay (6 * tck + 20) nano seconds */ udelay(1); switch (chan->type) { case IIO_ANGL: - ad2s1210_set_mode(MOD_POS, st); + ret = ad2s1210_set_mode(st, MOD_POS); break; case IIO_ANGL_VEL: - ad2s1210_set_mode(MOD_VEL, st); + ret = ad2s1210_set_mode(st, MOD_VEL); break; default: ret = -EINVAL; @@ -432,7 +423,7 @@ static int ad2s1210_single_conversion(struct ad2s1210_state *st, } error_ret: - gpiod_set_value(st->gpios[AD2S1210_SAMPLE], 1); + gpiod_set_value(st->sample_gpio, 0); /* delay (2 * tck + 20) nano seconds */ udelay(1); mutex_unlock(&st->lock); @@ -546,7 +537,9 @@ static int ad2s1210_initial(struct ad2s1210_state *st) int ret; mutex_lock(&st->lock); - ad2s1210_set_resolution_pin(st); + ret = ad2s1210_set_resolution_gpios(st, st->resolution); + if (ret < 0) + goto error_ret; /* Use default config register value plus resolution from devicetree. */ data = FIELD_PREP(AD2S1210_PHASE_LOCK_RANGE_44, 1); @@ -612,20 +605,34 @@ static int ad2s1210_setup_clocks(struct ad2s1210_state *st) static int ad2s1210_setup_gpios(struct ad2s1210_state *st) { - struct spi_device *spi = st->sdev; - int i, ret; - - for (i = 0; i < ARRAY_SIZE(gpios); i++) { - st->gpios[i] = devm_gpiod_get(&spi->dev, gpios[i].name, - gpios[i].flags); - if (IS_ERR(st->gpios[i])) { - ret = PTR_ERR(st->gpios[i]); - dev_err(&spi->dev, - "ad2s1210: failed to request %s GPIO: %d\n", - gpios[i].name, ret); - return ret; - } - } + struct device *dev = &st->sdev->dev; + + /* should not be sampling on startup */ + st->sample_gpio = devm_gpiod_get(dev, "sample", GPIOD_OUT_LOW); + if (IS_ERR(st->sample_gpio)) + return dev_err_probe(dev, PTR_ERR(st->sample_gpio), + "failed to request sample GPIO\n"); + + /* both pins high means that we start in config mode */ + st->mode_gpios = devm_gpiod_get_array(dev, "mode", GPIOD_OUT_HIGH); + if (IS_ERR(st->mode_gpios)) + return dev_err_probe(dev, PTR_ERR(st->mode_gpios), + "failed to request mode GPIOs\n"); + + if (st->mode_gpios->ndescs != 2) + return dev_err_probe(dev, -EINVAL, + "requires exactly 2 mode-gpios\n"); + + /* both pins high means that we start with 16-bit resolution */ + st->resolution_gpios = devm_gpiod_get_array(dev, "resolution", + GPIOD_OUT_HIGH); + if (IS_ERR(st->resolution_gpios)) + return dev_err_probe(dev, PTR_ERR(st->resolution_gpios), + "failed to request resolution GPIOs\n"); + + if (st->resolution_gpios->ndescs != 2) + return dev_err_probe(dev, -EINVAL, + "requires exactly 2 resolution-gpios\n"); return 0; } @@ -690,7 +697,6 @@ static int ad2s1210_probe(struct spi_device *spi) mutex_init(&st->lock); st->sdev = spi; st->hysteresis = true; - st->mode = MOD_CONFIG; st->resolution = 12; st->fexcit = AD2S1210_DEF_EXCIT; -- cgit v1.2.3