Re: [PATCH 05/11] iio: pressure-core: st: Describe LPS331AP definesby name

From: Lee Jones
Date: Thu Sep 05 2013 - 03:38:50 EST


> > They're currently named *_1_*, for 'Sensor 1', but the code will be much
> > more readable if we use the naming convention *_LPS331AP_* instead.
> You are right, but the reason is to maintain the same structure of the
> other sensors drivers (like accel, gyro and magn). Often some sensors
> can use the same data and using 1,2,... I think it's more general.

I've just coded this up for the pressure sensor [1] and in my opinion it
looks pretty ugly. We save 5 lines in this usecase, but we're
separating out some of the register addresses from the masks
etc.

Besides some code space #defines don't actually cost anything, so
unless the register set is almost identical I'd suggest putting them
in a header file out the way and separating them out like in the
original patch. I personally think it makes things so much clearer for
the reader.

I haven't looked at the other sensors yet, so perhaps we need to
evaluate this on a case by case basis, but certainly for this driver,
as we only support two sensors currently and for the sake of 5 lines I
think it's better to have them clearly defined per-sensor.

What do you think?

[1]:

/* GROUP VALUES SENSOR */
#define ST_PRESS_1_ODR_ADDR 0x20
#define ST_PRESS_1_ODR_AVL_1HZ_VAL 0x01
#define ST_PRESS_1_PW_ADDR 0x20
#define ST_PRESS_1_BDU_ADDR 0x20
#define ST_PRESS_1_MULTIREAD_BIT true

/* CUSTOM VALUES FOR LPS331AP SENSOR */
#define ST_PRESS_LPS331AP_WAI_EXP 0xbb
#define ST_PRESS_LPS331AP_ODR_MASK 0x70
#define ST_PRESS_LPS331AP_ODR_AVL_7HZ_VAL 0x05
#define ST_PRESS_LPS331AP_ODR_AVL_13HZ_VAL 0x06
#define ST_PRESS_LPS331AP_ODR_AVL_25HZ_VAL 0x07
#define ST_PRESS_LPS331AP_PW_MASK 0x80
#define ST_PRESS_LPS331AP_FS_ADDR 0x23
#define ST_PRESS_LPS331AP_FS_MASK 0x30
#define ST_PRESS_LPS331AP_FS_AVL_1260_VAL 0x00
#define ST_PRESS_LPS331AP_FS_AVL_1260_GAIN ST_PRESS_MBAR_TO_KPASCAL(244141)
#define ST_PRESS_LPS331AP_FS_AVL_TEMP_GAIN 2083000
#define ST_PRESS_LPS331AP_BDU_MASK 0x04
#define ST_PRESS_LPS331AP_DRDY_IRQ_ADDR 0x22
#define ST_PRESS_LPS331AP_DRDY_IRQ_MASK 0x04
#define ST_PRESS_LPS331AP_TEMP_OFFSET 42500
#define ST_PRESS_LPS331AP_OUT_XL_ADDR 0x28
#define ST_TEMP_LPS331AP_OUT_L_ADDR 0x2b

/* CUSTOM VALUES FOR LPS001WP SENSOR */
#define ST_PRESS_LPS001WP_WAI_EXP 0xba
#define ST_PRESS_LPS001WP_ODR_MASK 0x30
#define ST_PRESS_LPS001WP_ODR_AVL_7HZ_VAL 0x02
#define ST_PRESS_LPS001WP_ODR_AVL_13HZ_VAL 0x03
#define ST_PRESS_LPS001WP_PW_MASK 0x40
#define ST_PRESS_LPS001WP_BDU_MASK 0x04
#define ST_PRESS_LPS001WP_OUT_L_ADDR 0x28
#define ST_TEMP_LPS001WP_OUT_L_ADDR 0x2a

static const struct iio_chan_spec st_press_lsp331ap_channels[] = {
{
.type = IIO_PRESSURE,
.channel2 = IIO_NO_MOD,
.address = ST_PRESS_LPS331AP_OUT_XL_ADDR,
.scan_index = ST_SENSORS_SCAN_X,
.scan_type = {
.sign = 'u',
.realbits = 24,
.storagebits = 24,
.endianness = IIO_LE,
},
.info_mask_separate =
BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
.modified = 0,
},
{
.type = IIO_TEMP,
.channel2 = IIO_NO_MOD,
.address = ST_TEMP_LPS331AP_OUT_L_ADDR,
.scan_index = -1,
.scan_type = {
.sign = 'u',
.realbits = 16,
.storagebits = 16,
.endianness = IIO_LE,
},
.info_mask_separate =
BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_OFFSET),
.modified = 0,
},
IIO_CHAN_SOFT_TIMESTAMP(1)
};

static const struct iio_chan_spec st_press_lps001wp_channels[] = {
{
.type = IIO_PRESSURE,
.channel2 = IIO_NO_MOD,
.address = ST_PRESS_LPS001WP_OUT_L_ADDR,
.scan_index = ST_SENSORS_SCAN_X,
.scan_type = {
.sign = 'u',
.realbits = 16,
.storagebits = 16,
.endianness = IIO_LE,
},
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
.modified = 0,
},
{
.type = IIO_TEMP,
.channel2 = IIO_NO_MOD,
.address = ST_TEMP_LPS001WP_OUT_L_ADDR,
.scan_index = -1,
.scan_type = {
.sign = 'u',
.realbits = 16,
.storagebits = 16,
.endianness = IIO_LE,
},
.info_mask_separate =
BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_OFFSET),
.modified = 0,
},
IIO_CHAN_SOFT_TIMESTAMP(1)
};

static const struct st_sensors st_press_sensors[] = {
{
.wai = ST_PRESS_LPS331AP_WAI_EXP,
.sensors_supported = {
[0] = LPS331AP_PRESS_DEV_NAME,
},
.ch = (struct iio_chan_spec *)st_press_lsp331ap_channels,
.num_ch = ARRAY_SIZE(st_press_lsp331ap_channels),
.odr = {
.addr = ST_PRESS_1_ODR_ADDR,
.mask = ST_PRESS_LPS331AP_ODR_MASK,
.odr_avl = {
{ 1, ST_PRESS_1_ODR_AVL_1HZ_VAL, },
{ 7, ST_PRESS_LPS331AP_ODR_AVL_7HZ_VAL, },
{ 13, ST_PRESS_LPS331AP_ODR_AVL_13HZ_VAL, },
{ 25, ST_PRESS_LPS331AP_ODR_AVL_25HZ_VAL, },
},
},
.pw = {
.addr = ST_PRESS_1_PW_ADDR,
.mask = ST_PRESS_LPS331AP_PW_MASK,
.value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
.value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
},
.fs = {
.addr = ST_PRESS_LPS331AP_FS_ADDR,
.mask = ST_PRESS_LPS331AP_FS_MASK,
.fs_avl = {
[0] = {
.num = ST_PRESS_FS_AVL_1260MB,
.value = ST_PRESS_LPS331AP_FS_AVL_1260_VAL,
.gain = ST_PRESS_LPS331AP_FS_AVL_1260_GAIN,
.gain2 = ST_PRESS_LPS331AP_FS_AVL_TEMP_GAIN,
},
},
},
.bdu = {
.addr = ST_PRESS_1_BDU_ADDR,
.mask = ST_PRESS_LPS331AP_BDU_MASK,
},
.drdy_irq = {
.addr = ST_PRESS_LPS331AP_DRDY_IRQ_ADDR,
.mask = ST_PRESS_LPS331AP_DRDY_IRQ_MASK,
},
.multi_read_bit = ST_PRESS_1_MULTIREAD_BIT,
.bootime = 2,
},
{
.wai = ST_PRESS_LPS001WP_WAI_EXP,
.sensors_supported = {
[0] = LPS001WP_PRESS_DEV_NAME,
},
.ch = (struct iio_chan_spec *)st_press_lps001wp_channels,
.num_ch = ARRAY_SIZE(st_press_lps001wp_channels),
.odr = {
.addr = ST_PRESS_1_ODR_ADDR,
.mask = ST_PRESS_LPS001WP_ODR_MASK,
.odr_avl = {
{ 1, ST_PRESS_1_ODR_AVL_1HZ_VAL, },
{ 7, ST_PRESS_LPS001WP_ODR_AVL_7HZ_VAL, },
{ 13, ST_PRESS_LPS001WP_ODR_AVL_13HZ_VAL, },
},
},
.pw = {
.addr = ST_PRESS_1_PW_ADDR,
.mask = ST_PRESS_LPS001WP_PW_MASK,
.value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
.value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
},
.fs = {
.addr = 0,
},
.bdu = {
.addr = ST_PRESS_1_BDU_ADDR,
.mask = ST_PRESS_LPS001WP_BDU_MASK,
},
.drdy_irq = {
.addr = 0,
},
.multi_read_bit = ST_PRESS_1_MULTIREAD_BIT,
.bootime = 2,
},
};


> > -/* CUSTOM VALUES FOR SENSOR 1 */
> > -#define ST_PRESS_1_WAI_EXP 0xbb
> > -#define ST_PRESS_1_ODR_ADDR 0x20
> > -#define ST_PRESS_1_ODR_MASK 0x70
> > -#define ST_PRESS_1_ODR_AVL_1HZ_VAL 0x01
> > -#define ST_PRESS_1_ODR_AVL_7HZ_VAL 0x05
> > -#define ST_PRESS_1_ODR_AVL_13HZ_VAL 0x06
> > -#define ST_PRESS_1_ODR_AVL_25HZ_VAL 0x07
> > -#define ST_PRESS_1_PW_ADDR 0x20
> > -#define ST_PRESS_1_PW_MASK 0x80
> > -#define ST_PRESS_1_FS_ADDR 0x23
> > -#define ST_PRESS_1_FS_MASK 0x30
> > -#define ST_PRESS_1_FS_AVL_1260_VAL 0x00
> > -#define ST_PRESS_1_FS_AVL_1260_GAIN ST_PRESS_MBAR_TO_KPASCAL(244141)
> > -#define ST_PRESS_1_FS_AVL_TEMP_GAIN 2083000
> > -#define ST_PRESS_1_BDU_ADDR 0x20
> > -#define ST_PRESS_1_BDU_MASK 0x04
> > -#define ST_PRESS_1_DRDY_IRQ_ADDR 0x22
> > -#define ST_PRESS_1_DRDY_IRQ_MASK 0x04
> > -#define ST_PRESS_1_MULTIREAD_BIT true
> > -#define ST_PRESS_1_TEMP_OFFSET 42500
> > +/* CUSTOM VALUES FOR LPS331AP SENSOR */
> > +#define ST_PRESS_LPS331AP_WAI_EXP 0xbb
> > +#define ST_PRESS_LPS331AP_ODR_ADDR 0x20
> > +#define ST_PRESS_LPS331AP_ODR_MASK 0x70
> > +#define ST_PRESS_LPS331AP_ODR_AVL_1HZ_VAL 0x01
> > +#define ST_PRESS_LPS331AP_ODR_AVL_7HZ_VAL 0x05
> > +#define ST_PRESS_LPS331AP_ODR_AVL_13HZ_VAL 0x06
> > +#define ST_PRESS_LPS331AP_ODR_AVL_25HZ_VAL 0x07
> > +#define ST_PRESS_LPS331AP_PW_ADDR 0x20
> > +#define ST_PRESS_LPS331AP_PW_MASK 0x80
> > +#define ST_PRESS_LPS331AP_FS_ADDR 0x23
> > +#define ST_PRESS_LPS331AP_FS_MASK 0x30
> > +#define ST_PRESS_LPS331AP_FS_AVL_1260_VAL 0x00
> > +#define ST_PRESS_LPS331AP_FS_AVL_1260_GAIN ST_PRESS_MBAR_TO_KPASCAL(244141)
> > +#define ST_PRESS_LPS331AP_FS_AVL_TEMP_GAIN 2083000
> > +#define ST_PRESS_LPS331AP_BDU_ADDR 0x20
> > +#define ST_PRESS_LPS331AP_BDU_MASK 0x04
> > +#define ST_PRESS_LPS331AP_DRDY_IRQ_ADDR 0x22
> > +#define ST_PRESS_LPS331AP_DRDY_IRQ_MASK 0x04
> > +#define ST_PRESS_LPS331AP_MULTIREAD_BIT true
> > +#define ST_PRESS_LPS331AP_TEMP_OFFSET 42500
> > +#define ST_PRESS_LPS331AP_OUT_XL_ADDR 0x28
> > +#define ST_TEMP_LPS331AP_OUT_L_ADDR 0x2b
> >
> > static const struct iio_chan_spec st_press_channels[] = {
> > ST_SENSORS_LSM_CHANNELS(IIO_PRESSURE,
> > BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
> > ST_SENSORS_SCAN_X, 0, IIO_NO_MOD, 'u', IIO_LE, 24, 24,
> > - ST_PRESS_DEFAULT_OUT_XL_ADDR),
> > + ST_PRESS_LPS331AP_OUT_XL_ADDR),
> > ST_SENSORS_LSM_CHANNELS(IIO_TEMP,
> > BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) |
> > BIT(IIO_CHAN_INFO_OFFSET),
> > -1, 0, IIO_NO_MOD, 's', IIO_LE, 16, 16,
> > - ST_TEMP_DEFAULT_OUT_L_ADDR),
> > + ST_TEMP_LPS331AP_OUT_L_ADDR),
> > IIO_CHAN_SOFT_TIMESTAMP(1)
> > };
> >
> > static const struct st_sensors st_press_sensors[] = {
> > {
> > - .wai = ST_PRESS_1_WAI_EXP,
> > + .wai = ST_PRESS_LPS331AP_WAI_EXP,
> > .sensors_supported = {
> > [0] = LPS331AP_PRESS_DEV_NAME,
> > },
> > .ch = (struct iio_chan_spec *)st_press_channels,
> > .odr = {
> > - .addr = ST_PRESS_1_ODR_ADDR,
> > - .mask = ST_PRESS_1_ODR_MASK,
> > + .addr = ST_PRESS_LPS331AP_ODR_ADDR,
> > + .mask = ST_PRESS_LPS331AP_ODR_MASK,
> > .odr_avl = {
> > - { 1, ST_PRESS_1_ODR_AVL_1HZ_VAL, },
> > - { 7, ST_PRESS_1_ODR_AVL_7HZ_VAL, },
> > - { 13, ST_PRESS_1_ODR_AVL_13HZ_VAL, },
> > - { 25, ST_PRESS_1_ODR_AVL_25HZ_VAL, },
> > + { 1, ST_PRESS_LPS331AP_ODR_AVL_1HZ_VAL, },
> > + { 7, ST_PRESS_LPS331AP_ODR_AVL_7HZ_VAL, },
> > + { 13, ST_PRESS_LPS331AP_ODR_AVL_13HZ_VAL, },
> > + { 25, ST_PRESS_LPS331AP_ODR_AVL_25HZ_VAL, },
> > },
> > },
> > .pw = {
> > - .addr = ST_PRESS_1_PW_ADDR,
> > - .mask = ST_PRESS_1_PW_MASK,
> > + .addr = ST_PRESS_LPS331AP_PW_ADDR,
> > + .mask = ST_PRESS_LPS331AP_PW_MASK,
> > .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE,
> > .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE,
> > },
> > .fs = {
> > - .addr = ST_PRESS_1_FS_ADDR,
> > - .mask = ST_PRESS_1_FS_MASK,
> > + .addr = ST_PRESS_LPS331AP_FS_ADDR,
> > + .mask = ST_PRESS_LPS331AP_FS_MASK,
> > .fs_avl = {
> > [0] = {
> > .num = ST_PRESS_FS_AVL_1260MB,
> > - .value = ST_PRESS_1_FS_AVL_1260_VAL,
> > - .gain = ST_PRESS_1_FS_AVL_1260_GAIN,
> > - .gain2 = ST_PRESS_1_FS_AVL_TEMP_GAIN,
> > + .value = ST_PRESS_LPS331AP_FS_AVL_1260_VAL,
> > + .gain = ST_PRESS_LPS331AP_FS_AVL_1260_GAIN,
> > + .gain2 = ST_PRESS_LPS331AP_FS_AVL_TEMP_GAIN,
> > },
> > },
> > },
> > .bdu = {
> > - .addr = ST_PRESS_1_BDU_ADDR,
> > - .mask = ST_PRESS_1_BDU_MASK,
> > + .addr = ST_PRESS_LPS331AP_BDU_ADDR,
> > + .mask = ST_PRESS_LPS331AP_BDU_MASK,
> > },
> > .drdy_irq = {
> > - .addr = ST_PRESS_1_DRDY_IRQ_ADDR,
> > - .mask = ST_PRESS_1_DRDY_IRQ_MASK,
> > + .addr = ST_PRESS_LPS331AP_DRDY_IRQ_ADDR,
> > + .mask = ST_PRESS_LPS331AP_DRDY_IRQ_MASK,
> > },
> > - .multi_read_bit = ST_PRESS_1_MULTIREAD_BIT,
> > + .multi_read_bit = ST_PRESS_LPS331AP_MULTIREAD_BIT,
> > .bootime = 2,
> > },
> > };

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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