Kionix KX132-1211 is a tri-axis 16-bit accelerometer that can support
ranges from ±2G to ±16G, digital output through I²C/SPI.
Add support for basic accelerometer features such as reading acceleration
via IIO using raw reads, triggered buffer (data-ready), or the WMI IRQ.

Datasheet: https://kionixfs.azureedge.net/en/document/KX132-1211-Technical-Reference-Manual-Rev-5.0.pdf
Acked-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mehdi Djait <mehdi.djait.k@gmail.com>
---
v6: 
- no changes

v5: 
- moved the position of u16 buf_smp_lvl_mask as suggested by Andy
- introduced buf_smp_lvl_mask in Patch 7 as suggested by Jonathan

v4: 
- added KX132_REG_CNTL5 to the volatile ranges
- added the kionix reserved regs to the read_only ranges
- removed KX132_REG_MAN_WAKEUP from the write_only ranges

v3:
- fixed the warning of the kernel test robot in kx132_get_fifo_bytes
	(invalid assignment: &=, left side has type restricted __le16
	right side has type unsigned short)

v2:
- mentioned the kx132-1211 in the Kconfig
- added a kx132-specific get_fifo_bytes function
- changed the device name from "kx132" to "kx132-1211

 drivers/iio/accel/Kconfig             |   8 +-
 drivers/iio/accel/kionix-kx022a-i2c.c |   2 +
 drivers/iio/accel/kionix-kx022a-spi.c |   2 +
 drivers/iio/accel/kionix-kx022a.c     | 162 ++++++++++++++++++++++++++
 drivers/iio/accel/kionix-kx022a.h     |  54 +++++++++
 5 files changed, 224 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index b6b45d359f28..d8cc6e6f2bb9 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -418,8 +418,8 @@ config IIO_KX022A_SPI
 	select IIO_KX022A
 	select REGMAP_SPI
 	help
-	  Enable support for the Kionix KX022A digital tri-axis
-	  accelerometer connected to I2C interface.
+	  Enable support for the Kionix KX022A, KX132-1211 digital tri-axis
+	  accelerometers connected to SPI interface.
 
 config IIO_KX022A_I2C
 	tristate "Kionix KX022A tri-axis digital accelerometer I2C interface"
@@ -427,8 +427,8 @@ config IIO_KX022A_I2C
 	select IIO_KX022A
 	select REGMAP_I2C
 	help
-	  Enable support for the Kionix KX022A digital tri-axis
-	  accelerometer connected to I2C interface.
+	  Enable support for the Kionix KX022A, KX132-1211 digital tri-axis
+	  accelerometers connected to I2C interface.
 
 config KXSD9
 	tristate "Kionix KXSD9 Accelerometer Driver"
diff --git a/drivers/iio/accel/kionix-kx022a-i2c.c b/drivers/iio/accel/kionix-kx022a-i2c.c
index c59558fc6493..0f4729c55d29 100644
--- a/drivers/iio/accel/kionix-kx022a-i2c.c
+++ b/drivers/iio/accel/kionix-kx022a-i2c.c
@@ -41,12 +41,14 @@ static int kx022a_i2c_probe(struct i2c_client *i2c)
 
 static const struct i2c_device_id kx022a_i2c_id[] = {
 	{ .name = "kx022a", .driver_data = (kernel_ulong_t)&kx022a_chip_info },
+	{ .name = "kx132-1211", .driver_data = (kernel_ulong_t)&kx132_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, kx022a_i2c_id);
 
 static const struct of_device_id kx022a_of_match[] = {
 	{ .compatible = "kionix,kx022a", .data = &kx022a_chip_info },
+	{ .compatible = "kionix,kx132-1211", .data = &kx132_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, kx022a_of_match);
diff --git a/drivers/iio/accel/kionix-kx022a-spi.c b/drivers/iio/accel/kionix-kx022a-spi.c
index 896b57866fc9..c7766492bcd9 100644
--- a/drivers/iio/accel/kionix-kx022a-spi.c
+++ b/drivers/iio/accel/kionix-kx022a-spi.c
@@ -37,12 +37,14 @@ static int kx022a_spi_probe(struct spi_device *spi)
 
 static const struct spi_device_id kx022a_id[] = {
 	{ .name = "kx022a", .driver_data = (kernel_ulong_t)&kx022a_chip_info },
+	{ .name = "kx132-1211", .driver_data = (kernel_ulong_t)&kx132_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, kx022a_id);
 
 static const struct of_device_id kx022a_of_match[] = {
 	{ .compatible = "kionix,kx022a", .data = &kx022a_chip_info },
+	{ .compatible = "kionix,kx132-1211", .data = &kx132_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, kx022a_of_match);
diff --git a/drivers/iio/accel/kionix-kx022a.c b/drivers/iio/accel/kionix-kx022a.c
index 0b0f14dca17f..9b8304978d84 100644
--- a/drivers/iio/accel/kionix-kx022a.c
+++ b/drivers/iio/accel/kionix-kx022a.c
@@ -150,6 +150,117 @@ static const struct regmap_config kx022a_regmap_config = {
 	.cache_type = REGCACHE_RBTREE,
 };
 
+/* Regmap configs kx132 */
+static const struct regmap_range kx132_volatile_ranges[] = {
+	{
+		.range_min = KX132_REG_XADP_L,
+		.range_max = KX132_REG_COTR,
+	}, {
+		.range_min = KX132_REG_TSCP,
+		.range_max = KX132_REG_INT_REL,
+	}, {
+		/* The reset bit will be cleared by sensor */
+		.range_min = KX132_REG_CNTL2,
+		.range_max = KX132_REG_CNTL2,
+	}, {
+		.range_min = KX132_REG_CNTL5,
+		.range_max = KX132_REG_CNTL5,
+	}, {
+		.range_min = KX132_REG_BUF_STATUS_1,
+		.range_max = KX132_REG_BUF_READ,
+	},
+};
+
+static const struct regmap_access_table kx132_volatile_regs = {
+	.yes_ranges = &kx132_volatile_ranges[0],
+	.n_yes_ranges = ARRAY_SIZE(kx132_volatile_ranges),
+};
+
+static const struct regmap_range kx132_precious_ranges[] = {
+	{
+		.range_min = KX132_REG_INT_REL,
+		.range_max = KX132_REG_INT_REL,
+	},
+};
+
+static const struct regmap_access_table kx132_precious_regs = {
+	.yes_ranges = &kx132_precious_ranges[0],
+	.n_yes_ranges = ARRAY_SIZE(kx132_precious_ranges),
+};
+
+static const struct regmap_range kx132_read_only_ranges[] = {
+	{
+		.range_min = KX132_REG_XADP_L,
+		.range_max = KX132_REG_INT_REL,
+	}, {
+		.range_min = KX132_REG_BUF_STATUS_1,
+		.range_max = KX132_REG_BUF_STATUS_2,
+	}, {
+		.range_min = KX132_REG_BUF_READ,
+		.range_max = KX132_REG_BUF_READ,
+	}, {
+		/* Kionix reserved registers: should not be written */
+		.range_min = 0x28,
+		.range_max = 0x28,
+	}, {
+		.range_min = 0x35,
+		.range_max = 0x36,
+	}, {
+		.range_min = 0x3c,
+		.range_max = 0x48,
+	}, {
+		.range_min = 0x4e,
+		.range_max = 0x5c,
+	}, {
+		.range_min = 0x77,
+		.range_max = 0x7f,
+	},
+};
+
+static const struct regmap_access_table kx132_ro_regs = {
+	.no_ranges = &kx132_read_only_ranges[0],
+	.n_no_ranges = ARRAY_SIZE(kx132_read_only_ranges),
+};
+
+static const struct regmap_range kx132_write_only_ranges[] = {
+	{
+		.range_min = KX132_REG_SELF_TEST,
+		.range_max = KX132_REG_SELF_TEST,
+	}, {
+		.range_min = KX132_REG_BUF_CLEAR,
+		.range_max = KX132_REG_BUF_CLEAR,
+	},
+};
+
+static const struct regmap_access_table kx132_wo_regs = {
+	.no_ranges = &kx132_write_only_ranges[0],
+	.n_no_ranges = ARRAY_SIZE(kx132_write_only_ranges),
+};
+
+static const struct regmap_range kx132_noinc_read_ranges[] = {
+	{
+		.range_min = KX132_REG_BUF_READ,
+		.range_max = KX132_REG_BUF_READ,
+	},
+};
+
+static const struct regmap_access_table kx132_nir_regs = {
+	.yes_ranges = &kx132_noinc_read_ranges[0],
+	.n_yes_ranges = ARRAY_SIZE(kx132_noinc_read_ranges),
+};
+
+static const struct regmap_config kx132_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.volatile_table = &kx132_volatile_regs,
+	.rd_table = &kx132_wo_regs,
+	.wr_table = &kx132_ro_regs,
+	.rd_noinc_table = &kx132_nir_regs,
+	.precious_table = &kx132_precious_regs,
+	.max_register = KX132_MAX_REGISTER,
+	.cache_type = REGCACHE_RBTREE,
+};
+
 struct kx022a_data {
 	struct regmap *regmap;
 	const struct kx022a_chip_info *chip_info;
@@ -239,6 +350,13 @@ static const struct iio_chan_spec kx022a_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(3),
 };
 
+static const struct iio_chan_spec kx132_channels[] = {
+	KX022A_ACCEL_CHAN(X, KX132_REG_XOUT_L, 0),
+	KX022A_ACCEL_CHAN(Y, KX132_REG_YOUT_L, 1),
+	KX022A_ACCEL_CHAN(Z, KX132_REG_ZOUT_L, 2),
+	IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
 /*
  * The sensor HW can support ODR up to 1600 Hz, which is beyond what most of the
  * Linux CPUs can handle without dropping samples. Also, the low power mode is
@@ -612,6 +730,24 @@ static int kx022a_get_fifo_bytes(struct kx022a_data *data)
 	return fifo_bytes;
 }
 
+static int kx132_get_fifo_bytes(struct kx022a_data *data)
+{
+	__le16 buf_status;
+	int ret, fifo_bytes;
+
+	ret = regmap_bulk_read(data->regmap, data->chip_info->buf_status1,
+			       &buf_status, sizeof(buf_status));
+	if (ret) {
+		dev_err(data->dev, "Error reading buffer status\n");
+		return ret;
+	}
+
+	fifo_bytes = le16_to_cpu(buf_status);
+	fifo_bytes &= data->chip_info->buf_smp_lvl_mask;
+
+	return fifo_bytes;
+}
+
 static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples,
 			       bool irq)
 {
@@ -1034,6 +1170,32 @@ const struct kx022a_chip_info kx022a_chip_info = {
 };
 EXPORT_SYMBOL_NS_GPL(kx022a_chip_info, IIO_KX022A);
 
+const struct kx022a_chip_info kx132_chip_info = {
+	.name		  = "kx132-1211",
+	.regmap_config	  = &kx132_regmap_config,
+	.channels	  = kx132_channels,
+	.num_channels	  = ARRAY_SIZE(kx132_channels),
+	.fifo_length	  = KX132_FIFO_LENGTH,
+	.who		  = KX132_REG_WHO,
+	.id		  = KX132_ID,
+	.cntl		  = KX132_REG_CNTL,
+	.cntl2		  = KX132_REG_CNTL2,
+	.odcntl		  = KX132_REG_ODCNTL,
+	.buf_cntl1	  = KX132_REG_BUF_CNTL1,
+	.buf_cntl2	  = KX132_REG_BUF_CNTL2,
+	.buf_clear	  = KX132_REG_BUF_CLEAR,
+	.buf_status1	  = KX132_REG_BUF_STATUS_1,
+	.buf_smp_lvl_mask = KX132_MASK_BUF_SMP_LVL,
+	.buf_read	  = KX132_REG_BUF_READ,
+	.inc1		  = KX132_REG_INC1,
+	.inc4		  = KX132_REG_INC4,
+	.inc5		  = KX132_REG_INC5,
+	.inc6		  = KX132_REG_INC6,
+	.xout_l		  = KX132_REG_XOUT_L,
+	.get_fifo_bytes	  = kx132_get_fifo_bytes,
+};
+EXPORT_SYMBOL_NS_GPL(kx132_chip_info, IIO_KX022A);
+
 int kx022a_probe_internal(struct device *dev, const struct kx022a_chip_info *chip_info)
 {
 	static const char * const regulator_names[] = {"io-vdd", "vdd"};
diff --git a/drivers/iio/accel/kionix-kx022a.h b/drivers/iio/accel/kionix-kx022a.h
index c9f9aee7e597..ea6202d29303 100644
--- a/drivers/iio/accel/kionix-kx022a.h
+++ b/drivers/iio/accel/kionix-kx022a.h
@@ -74,6 +74,57 @@
 #define KX022A_REG_SELF_TEST	0x60
 #define KX022A_MAX_REGISTER	0x60
 
+#define KX132_REG_WHO		0x13
+#define KX132_ID		0x3d
+
+#define KX132_FIFO_LENGTH	86
+
+#define KX132_REG_CNTL		0x1b
+#define KX132_REG_CNTL2		0x1c
+#define KX132_REG_CNTL5		0x1f
+#define KX132_MASK_RES		BIT(6)
+#define KX132_GSEL_2		0x0
+#define KX132_GSEL_4		BIT(3)
+#define KX132_GSEL_8		BIT(4)
+#define KX132_GSEL_16		GENMASK(4, 3)
+
+#define KX132_REG_INS2		0x17
+#define KX132_MASK_INS2_WMI	BIT(5)
+
+#define KX132_REG_XADP_L	0x02
+#define KX132_REG_XOUT_L	0x08
+#define KX132_REG_YOUT_L	0x0a
+#define KX132_REG_ZOUT_L	0x0c
+#define KX132_REG_COTR		0x12
+#define KX132_REG_TSCP		0x14
+#define KX132_REG_INT_REL	0x1a
+
+#define KX132_REG_ODCNTL	0x21
+
+#define KX132_REG_BTS_WUF_TH	0x4a
+
+#define KX132_REG_BUF_CNTL1	0x5e
+#define KX132_REG_BUF_CNTL2	0x5f
+#define KX132_REG_BUF_STATUS_1	0x60
+#define KX132_REG_BUF_STATUS_2	0x61
+#define KX132_MASK_BUF_SMP_LVL	GENMASK(9, 0)
+#define KX132_REG_BUF_CLEAR	0x62
+#define KX132_REG_BUF_READ	0x63
+#define KX132_ODR_SHIFT		3
+#define KX132_FIFO_MAX_WMI_TH	86
+
+#define KX132_REG_INC1		0x22
+#define KX132_REG_INC5		0x26
+#define KX132_REG_INC6		0x27
+#define KX132_IPOL_LOW		0
+#define KX132_IPOL_HIGH		KX022A_MASK_IPOL
+#define KX132_ITYP_PULSE	KX022A_MASK_ITYP
+
+#define KX132_REG_INC4		0x25
+
+#define KX132_REG_SELF_TEST	0x5d
+#define KX132_MAX_REGISTER	0x76
+
 struct device;
 
 struct kx022a_data;
@@ -86,6 +137,7 @@ struct kx022a_data;
  * @channels:		pointer to iio_chan_spec array
  * @num_channels:	number of iio_chan_spec channels
  * @fifo_length:	number of 16-bit samples in a full buffer
+ * @buf_smp_lvl_mask:	buffer sample level mask
  * @who:		WHO_AM_I register
  * @id:			WHO_AM_I register value
  * @cntl:		control register 1
@@ -109,6 +161,7 @@ struct kx022a_chip_info {
 	const struct iio_chan_spec *channels;
 	unsigned int num_channels;
 	unsigned int fifo_length;
+	u16 buf_smp_lvl_mask;
 	u8 who;
 	u8 id;
 	u8 cntl;
@@ -130,5 +183,6 @@ struct kx022a_chip_info {
 int kx022a_probe_internal(struct device *dev, const struct kx022a_chip_info *chip_info);
 
 extern const struct kx022a_chip_info kx022a_chip_info;
+extern const struct kx022a_chip_info kx132_chip_info;
 
 #endif
-- 
2.30.2

Hi again Mehdi,

Just one thing still crossed to my mind...

On 6/13/23 13:22, Mehdi Djait wrote:
> Kionix KX132-1211 is a tri-axis 16-bit accelerometer that can support
> ranges from ±2G to ±16G, digital output through I²C/SPI.
> Add support for basic accelerometer features such as reading acceleration
> via IIO using raw reads, triggered buffer (data-ready), or the WMI IRQ.
> 
> Datasheet: https://kionixfs.azureedge.net/en/document/KX132-1211-Technical-Reference-Manual-Rev-5.0.pdf
> Acked-by: Matti Vaittinen <mazziesaccount@gmail.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Mehdi Djait <mehdi.djait.k@gmail.com>
> ---


> +static int kx132_get_fifo_bytes(struct kx022a_data *data)
> +{
> +	__le16 buf_status;
> +	int ret, fifo_bytes;
> +
> +	ret = regmap_bulk_read(data->regmap, data->chip_info->buf_status1,
> +			       &buf_status, sizeof(buf_status));
> +	if (ret) {
> +		dev_err(data->dev, "Error reading buffer status\n");
> +		return ret;
> +	}
> +
> +	fifo_bytes = le16_to_cpu(buf_status);
> +	fifo_bytes &= data->chip_info->buf_smp_lvl_mask;

Does this mask guarantee the fifo_bytes can't be bigger than the 
allocated buffer no matter what is read from I2C?

I am asking this because it's not uncommon to see some noise in I2C, or 
read 0xff 0xff, ... if IC is for example resetting. Hence, I would sleep 
a tad better if I knew the fifo_bytes read from IC is not 100% trusted - 
but is verified against known maximum number of samples.

This does not matter with the KX022A because the size of max number of 
samples exceeds the value indicated by 0xff (the 8bit SMP_LVL register).

Please correct me if I am wrong but it seems to me we use 10bits of data 
from smp_lvl register on KX132. Hence, the maximum value if all bits are 
set is 1023. This equals to 1023/6bytes samples - which is roughly 170. 
I think the FIFO size was defined to be maximum of 86 samples on KX132 - 
which means that if we have some bogus value from I2C, we may overwrite 
allocated buffer. Hence we might want to ensure the fifo_bytes is never 
bigger than the fifo_length * KX022A_FIFO_SAMPLES_SIZE_BYTES - no matter 
what we read from I2C.

> +
> +	return fifo_bytes;
> +}
> +

Yours,
	-- Matti

-- 
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland

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