From 66fe531268f274310a052603fc298f6cc177489b Mon Sep 17 00:00:00 2001 From: William Breathitt Gray Date: Sat, 16 Sep 2023 07:20:31 -0400 Subject: iio: addac: stx104: Add 8254 Counter/Timer support The STX104 features an 8254 Counter/Timer chip providing three counter/timers which can be used for frequency measurement, frequency output, pulse width modulation, pulse width measurement, event count, etc. The STX104 provides a register bank selection to bank select between the 8254 Bank and the Indexed Register Array Bank; the Indexed Register Array is not utilized by this driver, so the 8254 Bank is selected unconditionally. Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/20230916112031.3634-1-william.gray@linaro.org Signed-off-by: Jonathan Cameron --- drivers/iio/addac/Kconfig | 1 + drivers/iio/addac/stx104.c | 61 ++++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 60 insertions(+), 2 deletions(-) (limited to 'drivers/iio/addac') diff --git a/drivers/iio/addac/Kconfig b/drivers/iio/addac/Kconfig index 877f9124803c..b2623881f0ec 100644 --- a/drivers/iio/addac/Kconfig +++ b/drivers/iio/addac/Kconfig @@ -38,6 +38,7 @@ config STX104 select REGMAP_MMIO select GPIOLIB select GPIO_REGMAP + select I8254 help Say yes here to build support for the Apex Embedded Systems STX104 integrated analog PC/104 card. diff --git a/drivers/iio/addac/stx104.c b/drivers/iio/addac/stx104.c index d1f7ce033b46..6946a65512ca 100644 --- a/drivers/iio/addac/stx104.c +++ b/drivers/iio/addac/stx104.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -55,6 +56,7 @@ MODULE_PARM_DESC(base, "Apex Embedded Systems STX104 base addresses"); #define STX104_ADC_STATUS (STX104_AIO_BASE + 0x8) #define STX104_ADC_CONTROL (STX104_AIO_BASE + 0x9) #define STX104_ADC_CONFIGURATION (STX104_AIO_BASE + 0x11) +#define STX104_I8254_BASE (STX104_AIO_BASE + 0x12) #define STX104_AIO_DATA_STRIDE 2 #define STX104_DAC_OFFSET(_channel) (STX104_DAC_BASE + STX104_AIO_DATA_STRIDE * (_channel)) @@ -77,6 +79,7 @@ MODULE_PARM_DESC(base, "Apex Embedded Systems STX104 base addresses"); /* ADC Configuration */ #define STX104_GAIN GENMASK(1, 0) #define STX104_ADBU BIT(2) +#define STX104_RBK GENMASK(7, 4) #define STX104_BIPOLAR 0 #define STX104_GAIN_X1 0 #define STX104_GAIN_X2 1 @@ -168,6 +171,32 @@ static const struct regmap_config dio_regmap_config = { .io_port = true, }; +static const struct regmap_range pit_wr_ranges[] = { + regmap_reg_range(0x0, 0x3), +}; +static const struct regmap_range pit_rd_ranges[] = { + regmap_reg_range(0x0, 0x2), +}; +static const struct regmap_access_table pit_wr_table = { + .yes_ranges = pit_wr_ranges, + .n_yes_ranges = ARRAY_SIZE(pit_wr_ranges), +}; +static const struct regmap_access_table pit_rd_table = { + .yes_ranges = pit_rd_ranges, + .n_yes_ranges = ARRAY_SIZE(pit_rd_ranges), +}; + +static const struct regmap_config pit_regmap_config = { + .name = "i8254", + .reg_bits = 8, + .reg_stride = 1, + .reg_base = STX104_I8254_BASE, + .val_bits = 8, + .io_port = true, + .wr_table = &pit_wr_table, + .rd_table = &pit_rd_table, +}; + static int stx104_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { @@ -339,6 +368,21 @@ static const char *stx104_names[STX104_NGPIO] = { "DIN0", "DIN1", "DIN2", "DIN3", "DOUT0", "DOUT1", "DOUT2", "DOUT3" }; +static int bank_select_i8254(struct regmap *map) +{ + const u8 select_i8254[] = { 0x3, 0xB, 0xA }; + size_t i; + int err; + + for (i = 0; i < ARRAY_SIZE(select_i8254); i++) { + err = regmap_write_bits(map, STX104_ADC_CONFIGURATION, STX104_RBK, select_i8254[i]); + if (err) + return err; + } + + return 0; +} + static int stx104_init_hw(struct stx104_iio *const priv) { int err; @@ -361,7 +405,7 @@ static int stx104_init_hw(struct stx104_iio *const priv) if (err) return err; - return 0; + return bank_select_i8254(priv->aio_ctl_map); } static int stx104_probe(struct device *dev, unsigned int id) @@ -369,6 +413,7 @@ static int stx104_probe(struct device *dev, unsigned int id) struct iio_dev *indio_dev; struct stx104_iio *priv; struct gpio_regmap_config gpio_config; + struct i8254_regmap_config pit_config; void __iomem *stx104_base; struct regmap *aio_ctl_map; struct regmap *aio_data_map; @@ -406,6 +451,11 @@ static int stx104_probe(struct device *dev, unsigned int id) return dev_err_probe(dev, PTR_ERR(dio_map), "Unable to initialize dio register map\n"); + pit_config.map = devm_regmap_init_mmio(dev, stx104_base, &pit_regmap_config); + if (IS_ERR(pit_config.map)) + return dev_err_probe(dev, PTR_ERR(pit_config.map), + "Unable to initialize i8254 register map\n"); + priv = iio_priv(indio_dev); priv->aio_ctl_map = aio_ctl_map; priv->aio_data_map = aio_data_map; @@ -449,7 +499,13 @@ static int stx104_probe(struct device *dev, unsigned int id) .drvdata = dio_map, }; - return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &gpio_config)); + err = PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &gpio_config)); + if (err) + return err; + + pit_config.parent = dev; + + return devm_i8254_regmap_register(dev, &pit_config); } static struct isa_driver stx104_driver = { @@ -464,3 +520,4 @@ module_isa_driver(stx104_driver, num_stx104); MODULE_AUTHOR("William Breathitt Gray "); MODULE_DESCRIPTION("Apex Embedded Systems STX104 IIO driver"); MODULE_LICENSE("GPL v2"); +MODULE_IMPORT_NS(I8254); -- cgit v1.2.3-70-g09d2