Re: [PATCH v4 5/7] iio: accel: kionix-kx022a: Refactor driver and add chip_info structure

From: Matti Vaittinen
Date: Fri May 26 2023 - 13:04:32 EST

On 5/26/23 17:30, Mehdi Djait wrote:
Add the chip_info structure to the driver's private data to hold all
the device specific infos.
Refactor the kx022a driver implementation to make it more generic and
extensible.

Signed-off-by: Mehdi Djait <mehdi.djait.k@xxxxxxxxx>
---
v4:
- allocating and freeing the buffer moved to the kx022a_fifo{enable,
disable} functions
- used the spi_get_device_match_data helper function

v3:
- added the change of the buffer's allocation in the __kx022a_fifo_flush
to this patch
- added the chip_info to the struct kx022a_data

v2:
- mentioned the introduction of the i2c_device_id table in the commit
- get i2c_/spi_get_device_id only when device get match fails
- removed the generic KX_define
- removed the kx022a_device_type enum
- added comments for the chip_info struct elements
- fixed errors pointed out by the kernel test robot

drivers/iio/accel/kionix-kx022a-i2c.c | 15 +++-
drivers/iio/accel/kionix-kx022a-spi.c | 11 ++-
drivers/iio/accel/kionix-kx022a.c | 118 +++++++++++++++++---------
drivers/iio/accel/kionix-kx022a.h | 53 +++++++++++-
4 files changed, 145 insertions(+), 52 deletions(-)

diff --git a/drivers/iio/accel/kionix-kx022a-i2c.c b/drivers/iio/accel/kionix-kx022a-i2c.c
index b5a85ce3a891..ce299d0446f7 100644
--- a/drivers/iio/accel/kionix-kx022a-i2c.c
+++ b/drivers/iio/accel/kionix-kx022a-i2c.c
@@ -15,6 +15,7 @@
static int kx022a_i2c_probe(struct i2c_client *i2c)
{
struct device *dev = &i2c->dev;
+ const struct kx022a_chip_info *chip_info;
struct regmap *regmap;
if (!i2c->irq) {
@@ -22,22 +23,28 @@ static int kx022a_i2c_probe(struct i2c_client *i2c)
return -EINVAL;
}
- regmap = devm_regmap_init_i2c(i2c, &kx022a_regmap);
+ chip_info = device_get_match_data(&i2c->dev);
+ if (!chip_info) {
+ const struct i2c_device_id *id = i2c_client_get_device_id(i2c);
+ chip_info = (const struct kx022a_chip_info *)id->driver_data;
+ }
+
+ regmap = devm_regmap_init_i2c(i2c, chip_info->regmap_config);
if (IS_ERR(regmap))
return dev_err_probe(dev, PTR_ERR(regmap),
"Failed to initialize Regmap\n");
- return kx022a_probe_internal(dev);
+ return kx022a_probe_internal(dev, chip_info);
}
static const struct i2c_device_id kx022a_i2c_id[] = {
- { .name = "kx022a" },
+ { .name = "kx022a", .driver_data = (kernel_ulong_t)&kx022a_chip_info },
{ }
};
MODULE_DEVICE_TABLE(i2c, kx022a_i2c_id);
static const struct of_device_id kx022a_of_match[] = {
- { .compatible = "kionix,kx022a", },
+ { .compatible = "kionix,kx022a", .data = &kx022a_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 9cd047f7b346..1e4b9d4b4b8d 100644
--- a/drivers/iio/accel/kionix-kx022a-spi.c
+++ b/drivers/iio/accel/kionix-kx022a-spi.c
@@ -15,6 +15,7 @@
static int kx022a_spi_probe(struct spi_device *spi)
{
struct device *dev = &spi->dev;
+ const struct kx022a_chip_info *chip_info;
struct regmap *regmap;
if (!spi->irq) {
@@ -22,22 +23,24 @@ static int kx022a_spi_probe(struct spi_device *spi)
return -EINVAL;
}
- regmap = devm_regmap_init_spi(spi, &kx022a_regmap);
+ chip_info = spi_get_device_match_data(spi);
+
+ regmap = devm_regmap_init_spi(spi, chip_info->regmap_config);
if (IS_ERR(regmap))
return dev_err_probe(dev, PTR_ERR(regmap),
"Failed to initialize Regmap\n");
- return kx022a_probe_internal(dev);
+ return kx022a_probe_internal(dev, chip_info);
}
static const struct spi_device_id kx022a_id[] = {
- { "kx022a" },
+ { .name = "kx022a", .driver_data = (kernel_ulong_t)&kx022a_chip_info },
{ }
};
MODULE_DEVICE_TABLE(spi, kx022a_id);
static const struct of_device_id kx022a_of_match[] = {
- { .compatible = "kionix,kx022a", },
+ { .compatible = "kionix,kx022a", .data = &kx022a_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 494e81ba1da9..69c22071c731 100644
--- a/drivers/iio/accel/kionix-kx022a.c
+++ b/drivers/iio/accel/kionix-kx022a.c
@@ -48,7 +48,7 @@ enum {
KX022A_STATE_FIFO,
};
-/* Regmap configs */
+/* kx022a Regmap configs */
static const struct regmap_range kx022a_volatile_ranges[] = {
{
.range_min = KX022A_REG_XHP_L,
@@ -138,7 +138,7 @@ static const struct regmap_access_table kx022a_nir_regs = {
.n_yes_ranges = ARRAY_SIZE(kx022a_noinc_read_ranges),
};
-const struct regmap_config kx022a_regmap = {
+static const struct regmap_config kx022a_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.volatile_table = &kx022a_volatile_regs,
@@ -149,9 +149,9 @@ const struct regmap_config kx022a_regmap = {
.max_register = KX022A_MAX_REGISTER,
.cache_type = REGCACHE_RBTREE,
};
-EXPORT_SYMBOL_NS_GPL(kx022a_regmap, IIO_KX022A);
struct kx022a_data {
+ const struct kx022a_chip_info *chip_info;
struct regmap *regmap;
struct iio_trigger *trig;
struct device *dev;
@@ -175,6 +175,8 @@ struct kx022a_data {
struct mutex mutex;
u8 watermark;
+ __le16 *fifo_buffer;
+
/* 3 x 16bit accel data + timestamp */
__le16 buffer[8] __aligned(IIO_DMA_MINALIGN);
struct {
@@ -208,7 +210,7 @@ static const struct iio_chan_spec_ext_info kx022a_ext_info[] = {
{ }
};
-#define KX022A_ACCEL_CHAN(axis, index) \
+#define KX022A_ACCEL_CHAN(axis, reg, index) \
{ \
.type = IIO_ACCEL, \
.modified = 1, \
@@ -220,7 +222,7 @@ static const struct iio_chan_spec_ext_info kx022a_ext_info[] = {
BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.ext_info = kx022a_ext_info, \
- .address = KX022A_REG_##axis##OUT_L, \
+ .address = reg, \
.scan_index = index, \
.scan_type = { \
.sign = 's', \
@@ -231,9 +233,9 @@ static const struct iio_chan_spec_ext_info kx022a_ext_info[] = {
}
static const struct iio_chan_spec kx022a_channels[] = {
- KX022A_ACCEL_CHAN(X, 0),
- KX022A_ACCEL_CHAN(Y, 1),
- KX022A_ACCEL_CHAN(Z, 2),
+ KX022A_ACCEL_CHAN(X, KX022A_REG_XOUT_L, 0),
+ KX022A_ACCEL_CHAN(Y, KX022A_REG_YOUT_L, 1),
+ KX022A_ACCEL_CHAN(Z, KX022A_REG_ZOUT_L, 2),
IIO_CHAN_SOFT_TIMESTAMP(3),
};
@@ -332,10 +334,10 @@ static int kx022a_turn_on_off_unlocked(struct kx022a_data *data, bool on)
int ret;
if (on)
- ret = regmap_set_bits(data->regmap, KX022A_REG_CNTL,
+ ret = regmap_set_bits(data->regmap, data->chip_info->cntl,
KX022A_MASK_PC1);
else
- ret = regmap_clear_bits(data->regmap, KX022A_REG_CNTL,
+ ret = regmap_clear_bits(data->regmap, data->chip_info->cntl,
KX022A_MASK_PC1);
if (ret)
dev_err(data->dev, "Turn %s fail %d\n", str_on_off(on), ret);
@@ -402,7 +404,7 @@ static int kx022a_write_raw(struct iio_dev *idev,
break;
ret = regmap_update_bits(data->regmap,
- KX022A_REG_ODCNTL,
+ data->chip_info->odcntl,
KX022A_MASK_ODR, n);
data->odr_ns = kx022a_odrs[n];
kx022a_turn_on_unlock(data);
@@ -423,7 +425,7 @@ static int kx022a_write_raw(struct iio_dev *idev,
if (ret)
break;
- ret = regmap_update_bits(data->regmap, KX022A_REG_CNTL,
+ ret = regmap_update_bits(data->regmap, data->chip_info->cntl,
KX022A_MASK_GSEL,
n << KX022A_GSEL_SHIFT);
kx022a_turn_on_unlock(data);
@@ -445,7 +447,7 @@ static int kx022a_fifo_set_wmi(struct kx022a_data *data)
threshold = data->watermark;
- return regmap_update_bits(data->regmap, KX022A_REG_BUF_CNTL1,
+ return regmap_update_bits(data->regmap, data->chip_info->buf_cntl1,
KX022A_MASK_WM_TH, threshold);
}
@@ -488,7 +490,7 @@ static int kx022a_read_raw(struct iio_dev *idev,
return ret;
case IIO_CHAN_INFO_SAMP_FREQ:
- ret = regmap_read(data->regmap, KX022A_REG_ODCNTL, &regval);
+ ret = regmap_read(data->regmap, data->chip_info->odcntl, &regval);
if (ret)
return ret;
@@ -503,7 +505,7 @@ static int kx022a_read_raw(struct iio_dev *idev,
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_SCALE:
- ret = regmap_read(data->regmap, KX022A_REG_CNTL, &regval);
+ ret = regmap_read(data->regmap, data->chip_info->cntl, &regval);
if (ret < 0)
return ret;
@@ -530,8 +532,8 @@ static int kx022a_set_watermark(struct iio_dev *idev, unsigned int val)
{
struct kx022a_data *data = iio_priv(idev);
- if (val > KX022A_FIFO_LENGTH)
- val = KX022A_FIFO_LENGTH;
+ if (val > data->chip_info->fifo_length)
+ val = data->chip_info->fifo_length;
mutex_lock(&data->mutex);
data->watermark = val;
@@ -592,7 +594,7 @@ static int kx022a_drop_fifo_contents(struct kx022a_data *data)
*/
data->timestamp = 0;
- return regmap_write(data->regmap, KX022A_REG_BUF_CLEAR, 0x0);
+ return regmap_write(data->regmap, data->chip_info->buf_clear, 0x0);
}
static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples,
@@ -600,7 +602,6 @@ static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples,
{
struct kx022a_data *data = iio_priv(idev);
struct device *dev = regmap_get_device(data->regmap);
- __le16 buffer[KX022A_FIFO_LENGTH * 3];
uint64_t sample_period;
int count, fifo_bytes;
bool renable = false;
@@ -679,13 +680,13 @@ static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples,
}
fifo_bytes = count * KX022A_FIFO_SAMPLES_SIZE_BYTES;
- ret = regmap_noinc_read(data->regmap, KX022A_REG_BUF_READ,
- &buffer[0], fifo_bytes);
+ ret = regmap_noinc_read(data->regmap, data->chip_info->buf_read,
+ &data->fifo_buffer[0], fifo_bytes);
if (ret)
goto renable_out;
for (i = 0; i < count; i++) {
- __le16 *sam = &buffer[i * 3];
+ __le16 *sam = &data->fifo_buffer[i * 3];
__le16 *chs;
int bit;
@@ -732,10 +733,10 @@ static const struct iio_info kx022a_info = {
static int kx022a_set_drdy_irq(struct kx022a_data *data, bool en)
{
if (en)
- return regmap_set_bits(data->regmap, KX022A_REG_CNTL,
+ return regmap_set_bits(data->regmap, data->chip_info->cntl,
KX022A_MASK_DRDY);
- return regmap_clear_bits(data->regmap, KX022A_REG_CNTL,
+ return regmap_clear_bits(data->regmap, data->chip_info->cntl,
KX022A_MASK_DRDY);
}
@@ -762,6 +763,8 @@ static int kx022a_fifo_disable(struct kx022a_data *data)
{
int ret = 0;
+ kfree(data->fifo_buffer);

Should we have the kfree only after the sensor is disabled? I wonder if we in theory have here a time window where the buffer is freed but the measurement is still running and - with a lots of bad luck - can result measurement being written to a freed buffer? Perhaps move the kfree to be done only after the measurement has been stopped?

Other than that, this is looking good to me.

+
ret = kx022a_turn_off_lock(data);
if (ret)
return ret;
@@ -770,7 +773,7 @@ static int kx022a_fifo_disable(struct kx022a_data *data)
if (ret)
goto unlock_out;
- ret = regmap_clear_bits(data->regmap, KX022A_REG_BUF_CNTL2,
+ ret = regmap_clear_bits(data->regmap, data->chip_info->buf_cntl2,
KX022A_MASK_BUF_EN);
if (ret)
goto unlock_out;
@@ -801,6 +804,12 @@ static int kx022a_fifo_enable(struct kx022a_data *data)
{
int ret;
+ data->fifo_buffer = kmalloc(data->chip_info->fifo_length *
+ KX022A_FIFO_SAMPLES_SIZE_BYTES, GFP_KERNEL);
+
+ if (!data->fifo_buffer)
+ return -ENOMEM;
+
ret = kx022a_turn_off_lock(data);
if (ret)
return ret;
@@ -811,7 +820,7 @@ static int kx022a_fifo_enable(struct kx022a_data *data)
goto unlock_out;
/* Enable buffer */
- ret = regmap_set_bits(data->regmap, KX022A_REG_BUF_CNTL2,
+ ret = regmap_set_bits(data->regmap, data->chip_info->buf_cntl2,
KX022A_MASK_BUF_EN);
if (ret)
goto unlock_out;
@@ -857,7 +866,7 @@ static irqreturn_t kx022a_trigger_handler(int irq, void *p)
struct kx022a_data *data = iio_priv(idev);
int ret;
- ret = regmap_bulk_read(data->regmap, KX022A_REG_XOUT_L, data->buffer,
+ ret = regmap_bulk_read(data->regmap, data->chip_info->xout_l, data->buffer,
KX022A_FIFO_SAMPLES_SIZE_BYTES);
if (ret < 0)
goto err_read;
@@ -905,7 +914,7 @@ static irqreturn_t kx022a_irq_thread_handler(int irq, void *private)
if (data->state & KX022A_STATE_FIFO) {
int ok;
- ok = __kx022a_fifo_flush(idev, KX022A_FIFO_LENGTH, true);
+ ok = __kx022a_fifo_flush(idev, data->chip_info->fifo_length, true);
if (ok > 0)
ret = IRQ_HANDLED;
}
@@ -958,7 +967,7 @@ static int kx022a_chip_init(struct kx022a_data *data)
int ret, val;
/* Reset the senor */
- ret = regmap_write(data->regmap, KX022A_REG_CNTL2, KX022A_MASK_SRST);
+ ret = regmap_write(data->regmap, data->chip_info->cntl2, KX022A_MASK_SRST);
if (ret)
return ret;
@@ -968,7 +977,7 @@ static int kx022a_chip_init(struct kx022a_data *data)
*/
msleep(1);
- ret = regmap_read_poll_timeout(data->regmap, KX022A_REG_CNTL2, val,
+ ret = regmap_read_poll_timeout(data->regmap, data->chip_info->cntl2, val,
!(val & KX022A_MASK_SRST),
KX022A_SOFT_RESET_WAIT_TIME_US,
KX022A_SOFT_RESET_TOTAL_WAIT_TIME_US);
@@ -978,14 +987,14 @@ static int kx022a_chip_init(struct kx022a_data *data)
return ret;
}
- ret = regmap_reinit_cache(data->regmap, &kx022a_regmap);
+ ret = regmap_reinit_cache(data->regmap, data->chip_info->regmap_config);
if (ret) {
dev_err(data->dev, "Failed to reinit reg cache\n");
return ret;
}
/* set data res 16bit */
- ret = regmap_set_bits(data->regmap, KX022A_REG_BUF_CNTL2,
+ ret = regmap_set_bits(data->regmap, data->chip_info->buf_cntl2,
KX022A_MASK_BRES16);
if (ret) {
dev_err(data->dev, "Failed to set data resolution\n");
@@ -995,7 +1004,31 @@ static int kx022a_chip_init(struct kx022a_data *data)
return kx022a_prepare_irq_pin(data);
}
-int kx022a_probe_internal(struct device *dev)
+const struct kx022a_chip_info kx022a_chip_info = {
+ .name = "kx022-accel",
+ .regmap_config = &kx022a_regmap_config,
+ .channels = kx022a_channels,
+ .num_channels = ARRAY_SIZE(kx022a_channels),
+ .fifo_length = KX022A_FIFO_LENGTH,
+ .who = KX022A_REG_WHO,
+ .id = KX022A_ID,
+ .cntl = KX022A_REG_CNTL,
+ .cntl2 = KX022A_REG_CNTL2,
+ .odcntl = KX022A_REG_ODCNTL,
+ .buf_cntl1 = KX022A_REG_BUF_CNTL1,
+ .buf_cntl2 = KX022A_REG_BUF_CNTL2,
+ .buf_clear = KX022A_REG_BUF_CLEAR,
+ .buf_status1 = KX022A_REG_BUF_STATUS_1,
+ .buf_read = KX022A_REG_BUF_READ,
+ .inc1 = KX022A_REG_INC1,
+ .inc4 = KX022A_REG_INC4,
+ .inc5 = KX022A_REG_INC5,
+ .inc6 = KX022A_REG_INC6,
+ .xout_l = KX022A_REG_XOUT_L,
+};
+EXPORT_SYMBOL_NS_GPL(kx022a_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"};
struct iio_trigger *indio_trig;
@@ -1022,6 +1055,7 @@ int kx022a_probe_internal(struct device *dev)
return -ENOMEM;
data = iio_priv(idev);
+ data->chip_info = chip_info;
/*
* VDD is the analog and digital domain voltage supply and
@@ -1032,24 +1066,24 @@ int kx022a_probe_internal(struct device *dev)
if (ret && ret != -ENODEV)
return dev_err_probe(dev, ret, "failed to enable regulator\n");
- ret = regmap_read(regmap, KX022A_REG_WHO, &chip_id);
+ ret = regmap_read(regmap, chip_info->who, &chip_id);
if (ret)
return dev_err_probe(dev, ret, "Failed to access sensor\n");
- if (chip_id != KX022A_ID)
+ if (chip_id != chip_info->id)
dev_warn(dev, "unknown device 0x%x\n", chip_id);
irq = fwnode_irq_get_byname(fwnode, "INT1");
if (irq > 0) {
- data->inc_reg = KX022A_REG_INC1;
- data->ien_reg = KX022A_REG_INC4;
+ data->inc_reg = chip_info->inc1;
+ data->ien_reg = chip_info->inc4;
} else {
irq = fwnode_irq_get_byname(fwnode, "INT2");
if (irq <= 0)
return dev_err_probe(dev, irq, "No suitable IRQ\n");
- data->inc_reg = KX022A_REG_INC5;
- data->ien_reg = KX022A_REG_INC6;
+ data->inc_reg = chip_info->inc5;
+ data->ien_reg = chip_info->inc6;
}
data->regmap = regmap;
@@ -1058,9 +1092,9 @@ int kx022a_probe_internal(struct device *dev)
data->odr_ns = KX022A_DEFAULT_PERIOD_NS;
mutex_init(&data->mutex);
- idev->channels = kx022a_channels;
- idev->num_channels = ARRAY_SIZE(kx022a_channels);
- idev->name = "kx022-accel";
+ idev->channels = chip_info->channels;
+ idev->num_channels = chip_info->num_channels;
+ idev->name = chip_info->name;
idev->info = &kx022a_info;
idev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
idev->available_scan_masks = kx022a_scan_masks;
diff --git a/drivers/iio/accel/kionix-kx022a.h b/drivers/iio/accel/kionix-kx022a.h
index 12424649d438..c23b6f03409e 100644
--- a/drivers/iio/accel/kionix-kx022a.h
+++ b/drivers/iio/accel/kionix-kx022a.h
@@ -76,7 +76,56 @@
struct device;
-int kx022a_probe_internal(struct device *dev);
-extern const struct regmap_config kx022a_regmap;
+/**
+ * struct kx022a_chip_info - Kionix accelerometer chip specific information
+ *
+ * @name: name of the device
+ * @regmap_config: pointer to register map configuration
+ * @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
+ * @who: WHO_AM_I register
+ * @id: WHO_AM_I register value
+ * @cntl: control register 1
+ * @cntl2: control register 2
+ * @odcntl: output data control register
+ * @buf_cntl1: buffer control register 1
+ * @buf_cntl2: buffer control register 2
+ * @buf_clear: buffer clear register
+ * @buf_status1: buffer status register 1
+ * @buf_read: buffer read register
+ * @inc1: interrupt control register 1
+ * @inc4: interrupt control register 4
+ * @inc5: interrupt control register 5
+ * @inc6: interrupt control register 6
+ * @xout_l: x-axis output least significant byte
+ */
+struct kx022a_chip_info {
+ const char *name;
+ const struct regmap_config *regmap_config;
+ const struct iio_chan_spec *channels;
+ unsigned int num_channels;
+ unsigned int fifo_length;
+ u8 who;
+ u8 id;
+ u8 cntl;
+ u8 cntl2;
+ u8 odcntl;
+ u8 buf_cntl1;
+ u8 buf_cntl2;
+ u8 buf_clear;
+ u8 buf_status1;
+ u16 buf_smp_lvl_mask;
+ u8 buf_read;
+ u8 inc1;
+ u8 inc4;
+ u8 inc5;
+ u8 inc6;
+ u8 xout_l;
+};
+
+int kx022a_probe_internal(struct device *dev, const struct kx022a_chip_info *chip_info);
+
+extern const struct kx022a_chip_info kx022a_chip_info;
#endif

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

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