[PATCH v2 1/4] hwmon: (lm75) Create structure to save all the configuration parameters.

From: Iker Perez
Date: Thu Aug 08 2019 - 04:03:24 EST


From: Iker Perez del Palomar Sustatxa <iker.perez@xxxxxxxxxxxxxxx>

* Add to lm75_data kind field to store the kind of device the driver is
working with.
* Add an structure to store the configuration parameters of all the
supported devices.
* Delete resolution_limits from lm75_data and include them in the structure
described above.
* Add a pointer to the configuration parameters structure to be used as a
reference to obtain the parameters.
* Delete switch-case approach to get the device configuration parameters.
* The structure is cleaner and easier to maintain.

Signed-off-by: Iker Perez del Palomar Sustatxa <iker.perez@xxxxxxxxxxxxxxx>
---

Changes since v1:
- In the lm75_params structure documentation there have been the next changes:
- @resolution has been corrected to @default_resolution.
- @resolution_limits description has been corrected.
- pct2075 device's parameters has been included in device_params structure.

drivers/hwmon/lm75.c | 282 ++++++++++++++++++++++++++++++++-------------------
1 file changed, 176 insertions(+), 106 deletions(-)

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index a2d3f2ce3e1d..65a1131bfa7e 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -18,7 +18,6 @@
#include <linux/regmap.h>
#include "lm75.h"

-
/*
* This driver handles the LM75 and compatible digital temperature sensors.
*/
@@ -51,6 +50,28 @@ enum lm75_type { /* keep sorted in alphabetical order */
tmp75c,
};

+/**
+ * struct lm75_params - lm75 configuration parameters.
+ * @set_mask: Bits to set in configuration register when configuring
+ * the chip.
+ * @clr_mask: Bits to clear in configuration register when configuring
+ * the chip.
+ * @default_resolution: Default number of bits to represent the temperature
+ * value.
+ * @resolution_limits: Limit register resolution. Optional. Should be set if
+ * the resolution of limit registers does not match the
+ * resolution of the temperature register.
+ * default_sample_time: Sample time to be set by default.
+ */
+
+struct lm75_params {
+ u8 set_mask;
+ u8 clr_mask;
+ u8 default_resolution;
+ u8 resolution_limits;
+ unsigned int default_sample_time;
+};
+
/* Addresses scanned */
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
@@ -63,15 +84,151 @@ static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,

/* Each client has this additional data */
struct lm75_data {
- struct i2c_client *client;
- struct regmap *regmap;
- u8 orig_conf;
- u8 resolution; /* In bits, between 9 and 16 */
- u8 resolution_limits;
- unsigned int sample_time; /* In ms */
+ struct i2c_client *client;
+ struct regmap *regmap;
+ u8 orig_conf;
+ u8 current_conf;
+ u8 resolution; /* In bits, 9 to 16 */
+ unsigned int sample_time; /* In ms */
+ enum lm75_type kind;
+ const struct lm75_params *params;
};

/*-----------------------------------------------------------------------*/
+/* The structure below stores the configuration values of the supported devices.
+ * In case of being supported multiple configurations, the default one must
+ * always be the first element of the array
+ */
+static const struct lm75_params device_params[] = {
+ [adt75] = {
+ .clr_mask = 1 << 5, /* not one-shot mode */
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 8,
+ },
+ [ds1775] = {
+ .clr_mask = 3 << 5,
+ .set_mask = 2 << 5, /* 11-bit mode */
+ .default_resolution = 11,
+ .default_sample_time = MSEC_PER_SEC,
+ },
+ [ds75] = {
+ .clr_mask = 3 << 5,
+ .set_mask = 2 << 5, /* 11-bit mode */
+ .default_resolution = 11,
+ .default_sample_time = MSEC_PER_SEC,
+ },
+ [stds75] = {
+ .clr_mask = 3 << 5,
+ .set_mask = 2 << 5, /* 11-bit mode */
+ .default_resolution = 11,
+ .default_sample_time = MSEC_PER_SEC,
+ },
+ [stlm75] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 5,
+ },
+ [ds7505] = {
+ .set_mask = 3 << 5, /* 12-bit mode*/
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 4,
+ },
+ [g751] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 2,
+ },
+ [lm75] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 2,
+ },
+ [lm75a] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 2,
+ },
+ [lm75b] = {
+ .default_resolution = 11,
+ .default_sample_time = MSEC_PER_SEC / 4,
+ },
+ [max6625] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 4,
+ },
+ [max6626] = {
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 4,
+ .resolution_limits = 9,
+ },
+ [max31725] = {
+ .default_resolution = 16,
+ .default_sample_time = MSEC_PER_SEC / 8,
+ },
+ [tcn75] = {
+ .default_resolution = 9,
+ .default_sample_time = MSEC_PER_SEC / 8,
+ },
+ [pct2075] = {
+ .default_resolution = 11,
+ .default_sample_time = MSEC_PER_SEC / 10,
+ },
+ [mcp980x] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode */
+ .default_resolution = 12,
+ .resolution_limits = 9,
+ .default_sample_time = MSEC_PER_SEC,
+ },
+ [tmp100] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode */
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC,
+ },
+ [tmp101] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode */
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC,
+ },
+ [tmp112] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* no one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 4,
+ },
+ [tmp105] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 2,
+ },
+ [tmp175] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 2,
+ },
+ [tmp275] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 2,
+ },
+ [tmp75] = {
+ .set_mask = 3 << 5, /* 12-bit mode */
+ .clr_mask = 1 << 7, /* not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 2,
+ },
+ [tmp75b] = { /* not one-shot mode, Conversion rate 37Hz */
+ .clr_mask = 1 << 7 | 3 << 5,
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 37,
+ },
+ [tmp75c] = {
+ .clr_mask = 1 << 5, /*not one-shot mode*/
+ .default_resolution = 12,
+ .default_sample_time = MSEC_PER_SEC / 4,
+ }
+};

static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
{
@@ -146,8 +303,8 @@ static int lm75_write(struct device *dev, enum hwmon_sensor_types type,
* Resolution of limit registers is assumed to be the same as the
* temperature input register resolution unless given explicitly.
*/
- if (data->resolution_limits)
- resolution = data->resolution_limits;
+ if (data->params->resolution_limits)
+ resolution = data->params->resolution_limits;
else
resolution = data->resolution;

@@ -239,7 +396,6 @@ lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
struct device *hwmon_dev;
struct lm75_data *data;
int status, err;
- u8 set_mask, clr_mask;
int new;
enum lm75_type kind;

@@ -257,6 +413,7 @@ lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
return -ENOMEM;

data->client = client;
+ data->kind = kind;

data->regmap = devm_regmap_init_i2c(client, &lm75_regmap_config);
if (IS_ERR(data->regmap))
@@ -265,109 +422,22 @@ lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
/* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
* Then tweak to be more precise when appropriate.
*/
- set_mask = 0;
- clr_mask = LM75_SHUTDOWN; /* continuous conversions */
-
- switch (kind) {
- case adt75:
- clr_mask |= 1 << 5; /* not one-shot mode */
- data->resolution = 12;
- data->sample_time = MSEC_PER_SEC / 8;
- break;
- case ds1775:
- case ds75:
- case stds75:
- clr_mask |= 3 << 5;
- set_mask |= 2 << 5; /* 11-bit mode */
- data->resolution = 11;
- data->sample_time = MSEC_PER_SEC;
- break;
- case stlm75:
- data->resolution = 9;
- data->sample_time = MSEC_PER_SEC / 5;
- break;
- case ds7505:
- set_mask |= 3 << 5; /* 12-bit mode */
- data->resolution = 12;
- data->sample_time = MSEC_PER_SEC / 4;
- break;
- case g751:
- case lm75:
- case lm75a:
- data->resolution = 9;
- data->sample_time = MSEC_PER_SEC / 2;
- break;
- case lm75b:
- data->resolution = 11;
- data->sample_time = MSEC_PER_SEC / 4;
- break;
- case max6625:
- data->resolution = 9;
- data->sample_time = MSEC_PER_SEC / 4;
- break;
- case max6626:
- data->resolution = 12;
- data->resolution_limits = 9;
- data->sample_time = MSEC_PER_SEC / 4;
- break;
- case max31725:
- data->resolution = 16;
- data->sample_time = MSEC_PER_SEC / 8;
- break;
- case tcn75:
- data->resolution = 9;
- data->sample_time = MSEC_PER_SEC / 8;
- break;
- case pct2075:
- data->resolution = 11;
- data->sample_time = MSEC_PER_SEC / 10;
- break;
- case mcp980x:
- data->resolution_limits = 9;
- /* fall through */
- case tmp100:
- case tmp101:
- set_mask |= 3 << 5; /* 12-bit mode */
- data->resolution = 12;
- data->sample_time = MSEC_PER_SEC;
- clr_mask |= 1 << 7; /* not one-shot mode */
- break;
- case tmp112:
- set_mask |= 3 << 5; /* 12-bit mode */
- clr_mask |= 1 << 7; /* not one-shot mode */
- data->resolution = 12;
- data->sample_time = MSEC_PER_SEC / 4;
- break;
- case tmp105:
- case tmp175:
- case tmp275:
- case tmp75:
- set_mask |= 3 << 5; /* 12-bit mode */
- clr_mask |= 1 << 7; /* not one-shot mode */
- data->resolution = 12;
- data->sample_time = MSEC_PER_SEC / 2;
- break;
- case tmp75b: /* not one-shot mode, Conversion rate 37Hz */
- clr_mask |= 1 << 7 | 0x3 << 5;
- data->resolution = 12;
- data->sample_time = MSEC_PER_SEC / 37;
- break;
- case tmp75c:
- clr_mask |= 1 << 5; /* not one-shot mode */
- data->resolution = 12;
- data->sample_time = MSEC_PER_SEC / 4;
- break;
- }

- /* configure as specified */
+ data->params = &device_params[data->kind];
+
+ /* Save default sample time and resolution*/
+ data->sample_time = data->params->default_sample_time;
+ data->resolution = data->params->default_resolution;
+
+ /* Cache original configuration */
status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
if (status < 0) {
dev_dbg(dev, "Can't read config? %d\n", status);
return status;
}
data->orig_conf = status;
- new = status & ~clr_mask;
- new |= set_mask;
+ new = status & ~(data->params->clr_mask | LM75_SHUTDOWN);
+ new |= data->params->set_mask;
if (status != new)
i2c_smbus_write_byte_data(client, LM75_REG_CONF, new);

--
2.11.0