Re: [PATCH 1/2] iio: light: vcnl4000 add support for the VCNL4040 proximity and light sensor

Jonathan Cameron
2019-03-16T17:13:44Z

On Fri, 15 Mar 2019 14:54:24 -0700
"Angus Ainslie (Purism)" <angus@akkea.ca> wrote:

> The VCNL4040 is almost identical to the VCNL4200 as far as register
> layout goes but just need to check a different ID register location.
>
> This does change the initialization sequence of the VCNL4200 to use word
> writes instead of byte writes. The VCNL4200 datasheet says that word read
> and writes should be used to access the registers but I don't have a 4200
> to test with. The VCNL4040 doesn't initialize properly with the byte
> writes.
>
> devicetree hooks were also added.
>
> Signed-off-by: Angus Ainslie (Purism) <angus@akkea.ca>

Hi Angus,
A few things inline. Also.
1. Please break this up into a series. The word read thing (hopefully
after confirming it is fine on the older parts) should probably got in
as a fix for earlier kernels. Hence needs to be in its own patch.
2. DT hooks should be in their own patch.
3. After the above we should have a patch adding the new device support.

Mostly good though. Hopefully we'll get confirmation the word change
is fine on all the sensors. Peter?

Thanks,

Jonathan

> ---
> drivers/iio/light/vcnl4000.c | 89 ++++++++++++++++++++++++++++++------
> 1 file changed, 76 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
> index 04fd0d4b6f19..6e1f02aa6696 100644
> --- a/drivers/iio/light/vcnl4000.c
> +++ b/drivers/iio/light/vcnl4000.c
> @@ -10,13 +10,14 @@
> *
> * IIO driver for:
> * VCNL4000/10/20 (7-bit I2C slave address 0x13)
> + * VCNL4040 (7-bit I2C slave address 0x60)
> * VCNL4200 (7-bit I2C slave address 0x51)
> *
> * TODO:
> * allow to adjust IR current
> * proximity threshold and event handling
> * periodic ALS/proximity measurement (VCNL4010/20)
> - * interrupts (VCNL4010/20, VCNL4200)
> + * interrupts (VCNL4010/20/40, VCNL4200)
> */
>
> #include <linux/module.h>
> @@ -30,6 +31,7 @@
> #define VCNL4000_DRV_NAME "vcnl4000"
> #define VCNL4000_PROD_ID 0x01
> #define VCNL4010_PROD_ID 0x02 /* for VCNL4020, VCNL4010 */
> +#define VCNL4040_PROD_ID 0x86
> #define VCNL4200_PROD_ID 0x58
>
> #define VCNL4000_COMMAND 0x80 /* Command register */
> @@ -49,6 +51,8 @@
> #define VCNL4200_AL_DATA 0x09 /* Ambient light data */
> #define VCNL4200_DEV_ID 0x0e /* Device ID, slave address and version */
>
> +#define VCNL4040_DEV_ID 0x0c /* Device ID, slave address and version */
> +
> /* Bit masks for COMMAND register */
> #define VCNL4000_AL_RDY BIT(6) /* ALS data ready? */
> #define VCNL4000_PS_RDY BIT(5) /* proximity data ready? */
> @@ -58,6 +62,7 @@
> enum vcnl4000_device_ids {
> VCNL4000,
> VCNL4010,
> + VCNL4040,
> VCNL4200,
> };
>
> @@ -90,6 +95,7 @@ static const struct i2c_device_id vcnl4000_id[] = {
> { "vcnl4000", VCNL4000 },
> { "vcnl4010", VCNL4010 },
> { "vcnl4020", VCNL4010 },
> + { "vcnl4040", VCNL4040 },
> { "vcnl4200", VCNL4200 },
> { }
> };
> @@ -128,31 +134,56 @@ static int vcnl4000_init(struct vcnl4000_data *data)
>
> static int vcnl4200_init(struct vcnl4000_data *data)
> {
> - int ret;
> + int ret, id;
>
> ret = i2c_smbus_read_word_data(data->client, VCNL4200_DEV_ID);
> if (ret < 0)
> return ret;
>
> - if ((ret & 0xff) != VCNL4200_PROD_ID)
> - return -ENODEV;
> + id = ret & 0xff;
> +
> + if (id != VCNL4200_PROD_ID) {
> + ret = i2c_smbus_read_word_data(data->client, VCNL4040_DEV_ID);
> + if (ret < 0)
> + return ret;
> +
> + id = ret & 0xff;
> +
> + if (id != VCNL4040_PROD_ID)
> + return -ENODEV;
> +
> + }
> +
> + dev_dbg(&data->client->dev, "device id 0x%x", id);
>
> data->rev = (ret >> 8) & 0xf;
>
> /* Set defaults and enable both channels */
> - ret = i2c_smbus_write_byte_data(data->client, VCNL4200_AL_CONF, 0x00);
> + ret = i2c_smbus_write_word_data(data->client, VCNL4200_AL_CONF, 0x00);
> if (ret < 0)
> return ret;
> - ret = i2c_smbus_write_byte_data(data->client, VCNL4200_PS_CONF1, 0x00);
> + ret = i2c_smbus_write_word_data(data->client, VCNL4200_PS_CONF1, 0x00);
> if (ret < 0)
> return ret;
>
> + switch (id) {
> + case VCNL4200_PROD_ID:
> + /* Integration time is 50ms, but the experiments */
> + /* show 54ms in total. */
> + data->vcnl4200_al.sampling_rate = ktime_set(0, 54000 * 1000);
> + data->vcnl4200_ps.sampling_rate = ktime_set(0, 4200 * 1000);
> + break;
> + case VCNL4040_PROD_ID:
> + /* Integration time is 80ms, add 10ms. */
> + data->vcnl4200_al.sampling_rate = ktime_set(0, 100000 * 1000);
> + data->vcnl4200_ps.sampling_rate = ktime_set(0, 100000 * 1000);
> + break;
> + }
> +
> data->al_scale = 24000;
> data->vcnl4200_al.reg = VCNL4200_AL_DATA;
> data->vcnl4200_ps.reg = VCNL4200_PS_DATA;
> - /* Integration time is 50ms, but the experiments show 54ms in total. */
> - data->vcnl4200_al.sampling_rate = ktime_set(0, 54000 * 1000);
> - data->vcnl4200_ps.sampling_rate = ktime_set(0, 4200 * 1000);
> +
> data->vcnl4200_al.last_measurement = ktime_set(0, 0);
> data->vcnl4200_ps.last_measurement = ktime_set(0, 0);
> mutex_init(&data->vcnl4200_al.lock);
> @@ -194,8 +225,11 @@ static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
>
> ret = i2c_smbus_read_i2c_block_data(data->client,
> data_reg, sizeof(buf), (u8 *) &buf);
> - if (ret < 0)
> + if (ret < 0) {
> + dev_err(&data->client->dev, "smbus read failed 0x%02x\n",
> + ret);
Unrelated change... Should not be here.

> goto fail;
> + }
>
> mutex_unlock(&data->vcnl4000_lock);
> *val = be16_to_cpu(buf);
> @@ -216,6 +250,8 @@ static int vcnl4200_measure(struct vcnl4000_data *data,
>
> mutex_lock(&chan->lock);
>
> + ret = i2c_smbus_read_word_data(data->client, chan->reg);
> +
> next_measurement = ktime_add(chan->last_measurement,
> chan->sampling_rate);
> delta = ktime_us_delta(next_measurement, ktime_get());
> @@ -226,8 +262,12 @@ static int vcnl4200_measure(struct vcnl4000_data *data,
> mutex_unlock(&chan->lock);
>
> ret = i2c_smbus_read_word_data(data->client, chan->reg);
> - if (ret < 0)
> +
> + if (ret < 0) {
> + dev_err(&data->client->dev, "smbus read failed 0x%02x\n",
> + ret);
Unrelated change.

> return ret;
> + }
>
> *val = ret;
>
> @@ -271,6 +311,12 @@ static const struct vcnl4000_chip_spec vcnl4000_chip_spec_cfg[] = {
> .measure_light = vcnl4000_measure_light,
> .measure_proximity = vcnl4000_measure_proximity,
> },
> + [VCNL4040] = {
> + .prod = "VCNL4040",
> + .init = vcnl4200_init,
> + .measure_light = vcnl4200_measure_light,
> + .measure_proximity = vcnl4200_measure_proximity,
> + },
> [VCNL4200] = {
> .prod = "VCNL4200",
> .init = vcnl4200_init,
> @@ -350,7 +396,7 @@ static int vcnl4000_probe(struct i2c_client *client,
> if (ret < 0)
> return ret;
>
> - dev_dbg(&client->dev, "%s Ambient light/proximity sensor, Rev: %02x\n",
> + dev_err(&client->dev, "%s Ambient light/proximity sensor, Rev: %02x\n",
> data->chip_spec->prod, data->rev);
Unrelated change. It's also not an error!

>
> indio_dev->dev.parent = &client->dev;
> @@ -373,6 +419,23 @@ static struct i2c_driver vcnl4000_driver = {
>
> module_i2c_driver(vcnl4000_driver);
>
> +#ifdef CONFIG_OF
> +static const struct of_device_id vcnl_4000_of_match[] = {
> + {
> + .compatible = "vishay,vcnl4000",
> + .data = "VCNL4000",
> + },
> + {
> + .compatible = "vishay,vcnl4040",
> + .data = "VCNL4040",
> + },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, vcnl4000_of_match);
> +#else
> +#define vcnl_4000_of_match NULL
> +#endif
Don't bother with the guard barriers. The cost is small and we now
want the of_device_id table even on acpi platforms.

Also would expect this to be used as the match table.

> +
> MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
> -MODULE_DESCRIPTION("Vishay VCNL4000 proximity/ambient light sensor driver");
> +MODULE_DESCRIPTION("Vishay VCNL4xx0 proximity/ambient light sensor driver");
don't add wild cards. It goes wrong far too often.
> MODULE_LICENSE("GPL");