On 10/12/22 13:57, Naresh Solanki wrote:
max6639_platform_data is not used by any in-kernel driver and does not
address the MAX6639 fans separately.
Move to device tree configuration with explicit properties to configure
each fan.
Non-DT platform can still use this module with its default
configuration.
Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
---
drivers/hwmon/max6639.c | 205 +++++++++++++++++++++++++++++-----------
1 file changed, 152 insertions(+), 53 deletions(-)
diff --git a/drivers/hwmon/max6639.c b/drivers/hwmon/max6639.c
index 9b895402c80d..2fc096a00e21 100644
--- a/drivers/hwmon/max6639.c
+++ b/drivers/hwmon/max6639.c
@@ -19,7 +19,6 @@
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
-#include <linux/platform_data/max6639.h>
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END };
@@ -85,9 +84,9 @@ struct max6639_data {
u8 temp_ot[2]; /* OT Temperature, 0..255 C (->_emergency) */
/* Register values initialized only once */
- u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */
- u8 rpm_range; /* Index in above rpm_ranges table */
-
+ u8 ppr[2]; /* Pulses per rotation 0..3 for 1..4 ppr */
+ u8 rpm_range[2]; /* Index in above rpm_ranges table */
+ u8 pwm_polarity[2]; /* Fans PWM polarity, 0..1 */
/* Optional regulator for FAN supply */
struct regulator *reg;
};
@@ -319,7 +318,7 @@ static ssize_t fan_input_show(struct device *dev,
return PTR_ERR(data);
return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index],
- data->rpm_range));
+ data->rpm_range[attr->index]));
}
static ssize_t alarm_show(struct device *dev,
@@ -386,29 +385,39 @@ static struct attribute *max6639_attrs[] = {
ATTRIBUTE_GROUPS(max6639);
/*
- * returns respective index in rpm_ranges table
- * 1 by default on invalid range
+ * Get respective index in rpm_ranges table
*/
-static int rpm_range_to_reg(int range)
+static int rpm_range_to_index(struct device *dev, u8 *index, int rpm)
{
- int i;
-
- for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) {
- if (rpm_ranges[i] == range)
- return i;
+ if (rpm < 0)
+ return -EINVAL;
+
+ /* Set index based on chip support */
+ switch (rpm) {
+ case 0 ... 2000:
+ *index = 0;
+ break;
+ case 2001 ... 4000:
+ *index = 1;
+ break;
+ case 4001 ... 8000:
+ *index = 2;
+ break;
+ case 8001 ... 16000:
+ *index = 3;
+ break;
+ default:
+ /* Use max range for higher RPM */
+ dev_warn(dev, "RPM higher than supported range.");
It is illogical to complain about that but not about other invalid values.
+ *index = 3;
}
-
- return 1; /* default: 4000 RPM */
+ return 0;
The return value can be used both as error indicator (return value < 0)
and index (return value >= 0). It is not necessary to introduce a pointer.
}
static int max6639_init_client(struct i2c_client *client,
struct max6639_data *data)
{
- struct max6639_platform_data *max6639_info =
- dev_get_platdata(&client->dev);
- int i;
- int rpm_range = 1; /* default: 4000 RPM */
- int err;
+ int i, err;
/* Reset chip to default values, see below for GCONFIG setup */
err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG,
@@ -416,51 +425,32 @@ static int max6639_init_client(struct i2c_client *client,
if (err)
goto exit;
- /* Fans pulse per revolution is 2 by default */
- if (max6639_info && max6639_info->ppr > 0 &&
- max6639_info->ppr < 5)
- data->ppr = max6639_info->ppr;
- else
- data->ppr = 2;
- data->ppr -= 1;
-
- if (max6639_info)
- rpm_range = rpm_range_to_reg(max6639_info->rpm_range);
- data->rpm_range = rpm_range;
-
for (i = 0; i < 2; i++) {
/* Set Fan pulse per revolution */
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_FAN_PPR(i),
- data->ppr << 6);
+ data->ppr[i] << 6);
if (err)
goto exit;
/* Fans config PWM, RPM */
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_FAN_CONFIG1(i),
- MAX6639_FAN_CONFIG1_PWM | rpm_range);
+ MAX6639_FAN_CONFIG1_PWM | data->rpm_range[i]);
if (err)
goto exit;
- /* Fans PWM polarity high by default */
- if (max6639_info && max6639_info->pwm_polarity == 0)
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_CONFIG2a(i), 0x00);
- else
- err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_CONFIG2a(i), 0x02);
- if (err)
- goto exit;
+ /* Fans PWM polarity */
+ err = i2c_smbus_write_byte_data(client,
+ MAX6639_REG_FAN_CONFIG2a(i), data->pwm_polarity[i] ? 0x02 : 0x00);
/*
- * /THERM full speed enable,
+ * /THERM full speed disable,
* PWM frequency 25kHz, see also GCONFIG below
*/
err = i2c_smbus_write_byte_data(client,
- MAX6639_REG_FAN_CONFIG3(i),
- MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03);
+ MAX6639_REG_FAN_CONFIG3(i), 0x03);
if (err)
goto exit;
@@ -483,8 +473,6 @@ static int max6639_init_client(struct i2c_client *client,
if (err)
goto exit;
- /* PWM 120/120 (i.e. 100%) */
- data->pwm[i] = 120;
err = i2c_smbus_write_byte_data(client,
MAX6639_REG_TARGTDUTY(i), data->pwm[i]);
if (err)
@@ -524,12 +512,92 @@ static void max6639_regulator_disable(void *data)
regulator_disable(data);
}
+static int max6639_probe_child_from_dt(struct i2c_client *client,
+ struct device_node *child,
+ struct max6639_data *data)
+
+{
+ struct device *dev = &client->dev;
+ u32 i, val, maxrpm;
+ int err;
+
+ err = of_property_read_u32(child, "reg", &i);
+ if (err) {
+ dev_err(dev, "missing reg property of %pOFn\n", child);
+ return err;
+ }
+
+ if (i >= 2) {
+ dev_err(dev, "invalid reg %d of %pOFn\n", i, child);
+ return -EINVAL;
+ }
+
+ err = of_property_read_u32(child, "pulses-per-revolution", &val);
+ if (err) {
+ dev_err(dev, "missing pulses-per-revolution property of %pOFn\n", child);
+ return err;
+ }
+
+ if (val < 0 || val > 5) {
+ dev_err(dev, "invalid pulses-per-revolution %d of %pOFn\n", val, child);
+ return -EINVAL;
+ }
+ data->ppr[i] = val;
+
+ err = of_property_read_u32(child, "max-rpm", &maxrpm);
+ if (err) {
+ dev_err(dev, "missing max-rpm property of %pOFn\n", child);
+ return err;
+ }
+
+ err = rpm_range_to_index(dev, &data->rpm_range[i], maxrpm);
+ if (err) {
+ dev_err(dev, "invalid max-rpm %d of %pOFn\n", maxrpm, child);
+ return err;
+ }
+
+
Dual empty line.
+ err = of_property_read_u32(child, "target-rpm", &val);
+ /* Convert to PWM from provided target RPM */
+ if (!err && val != 0)
+ data->pwm[i] =
+ (u8)(val * 120 / maxrpm);
+
It is not acceptable for any of those missing properties to result
in errors. Use current chip values as default if values are not
provided.
+ data->pwm_polarity[i] = of_property_read_bool(child, "pwm-polarity-inverse");
+
+ return 0;
+}
+static int max6639_probe_from_dt(struct i2c_client *client, struct max6639_data *data)
+{
+ struct device *dev = &client->dev;
+ const struct device_node *np = dev->of_node;
+ struct device_node *child;
+ int err;
+
+ /* Compatible with non-DT platforms */
+ if (!np)
+ return 0;
+
+ for_each_child_of_node(np, child) {
+ if (strcmp(child->name, "fan"))
+ continue;
+
+ err = max6639_probe_child_from_dt(client, child, data);
+ if (err) {
+ of_node_put(child);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
static int max6639_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct max6639_data *data;
struct device *hwmon_dev;
- int err;
+ int err, i;
data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL);
if (!data)
@@ -539,9 +607,11 @@ static int max6639_probe(struct i2c_client *client)
data->reg = devm_regulator_get_optional(dev, "fan");
if (IS_ERR(data->reg)) {
- if (PTR_ERR(data->reg) != -ENODEV)
- return PTR_ERR(data->reg);
-
+ if (PTR_ERR(data->reg) != -ENODEV) {
+ err = (int)PTR_ERR(data->reg);
+ dev_warn(dev, "Failed looking up fan supply: %d\n", err);
This is an unrelated change. It is not common to issue a warning
in that situation, and I am not inclined to accept it. Besides,
the function can return -EPROBE_DEFER, and any messages associated
with that are unacceptable.
+ return err;
+ }
data->reg = NULL;
} else {
/* Spin up fans */
@@ -560,6 +630,24 @@ static int max6639_probe(struct i2c_client *client)
mutex_init(&data->update_lock);
+ /* default values */
+ for (i = 0; i < 2; i++) {
+ /* 4000 RPM */
+ data->rpm_range[i] = 1;
+ data->ppr[i] = 2;
+ data->pwm_polarity[i] = 1;
+ /* Max. temp. 80C/90C/100C */
+ data->temp_therm[i] = 80;
+ data->temp_alert[i] = 90;
+ data->temp_ot[i] = 100;
+ /* PWM 120/120 (i.e. 100%) */
+ data->pwm[i] = 120;
+ }
As I said, defaults are values currently programmed into the chip,
not some random values.
+
+ err = max6639_probe_from_dt(client, data);
+ if (err)
+ return err;
+
/* Initialize the max6639 chip */
err = max6639_init_client(client, data);
if (err < 0)
@@ -571,6 +659,7 @@ static int max6639_probe(struct i2c_client *client)
return PTR_ERR_OR_ZERO(hwmon_dev);
}
+#if IS_ENABLED(CONFIG_PM_SLEEP)
static int max6639_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
@@ -608,6 +697,7 @@ static int max6639_resume(struct device *dev)
return i2c_smbus_write_byte_data(client,
MAX6639_REG_GCONFIG, ret & ~MAX6639_GCONFIG_STANDBY);
}
+#endif
This can be done without #ifdef.
static const struct i2c_device_id max6639_id[] = {
{"max6639", 0},
@@ -616,13 +706,22 @@ static const struct i2c_device_id max6639_id[] = {
MODULE_DEVICE_TABLE(i2c, max6639_id);
-static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
+#ifdef CONFIG_OF
+static const struct of_device_id maxim_of_platform_match[] = {
+ {.compatible = "maxim,max6639"},
+ {},
+};
+MODULE_DEVICE_TABLE(of, maxim_of_platform_match);
+#endif
+
+static SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume);
static struct i2c_driver max6639_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "max6639",
.pm = pm_sleep_ptr(&max6639_pm_ops),
+ .of_match_table = of_match_ptr(maxim_of_platform_match),
},
.probe_new = max6639_probe,
.id_table = max6639_id,
