This change adds debugfs to read and write temperature sensor coefficients - g, h, j and cal5. The coefficients can vary between product and product, so it can be very useful to be able to modify them on the fly during the calibration process. e.g.: cat /sys/kernel/debug/940f23d0000.pvt/ts_coeff_cal5 4096 echo 83000 > sys/kernel/debug/940f23d0000.pvt/ts_coeff_g Signed-off-by: Eliav Farber <farbere@xxxxxxxxxx> --- V5 -> V4: - Return j coefficient to use debugfs_create_file() instead of debugfs_create_u32() because j is signed. V4 -> V3: - Remove check of the debugfs_create_dir() return value. - Use debugfs_create_u32() instead of debugfs_create_file(). - Return devm_add_action_or_reset() without checking return value and printing an error message on failure. drivers/hwmon/mr75203.c | 62 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) diff --git a/drivers/hwmon/mr75203.c b/drivers/hwmon/mr75203.c index 07668545c3ae..e6b49f810307 100644 --- a/drivers/hwmon/mr75203.c +++ b/drivers/hwmon/mr75203.c @@ -9,6 +9,7 @@ */ #include <linux/bits.h> #include <linux/clk.h> +#include <linux/debugfs.h> #include <linux/hwmon.h> #include <linux/module.h> #include <linux/mod_devicetable.h> @@ -170,6 +171,7 @@ struct pvt_device { struct regmap *v_map; struct clk *clk; struct reset_control *rst; + struct dentry *dbgfs_dir; struct voltage_device *vd; struct voltage_channels vm_channels; struct temp_coeff ts_coeff; @@ -179,6 +181,64 @@ struct pvt_device { u32 ip_freq; }; +static ssize_t pvt_ts_coeff_j_read(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct pvt_device *pvt = file->private_data; + unsigned int len; + char buf[13]; + + len = scnprintf(buf, sizeof(buf), "%d\n", pvt->ts_coeff.j); + + return simple_read_from_buffer(user_buf, count, ppos, buf, len); +} + +static ssize_t pvt_ts_coeff_j_write(struct file *file, + const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct pvt_device *pvt = file->private_data; + int ret; + + ret = kstrtos32_from_user(user_buf, count, 0, &pvt->ts_coeff.j); + if (ret) + return ret; + + return count; +} + +static const struct file_operations pvt_ts_coeff_j_fops = { + .read = pvt_ts_coeff_j_read, + .write = pvt_ts_coeff_j_write, + .open = simple_open, + .owner = THIS_MODULE, + .llseek = default_llseek, +}; + +static void devm_pvt_ts_dbgfs_remove(void *data) +{ + struct pvt_device *pvt = (struct pvt_device *)data; + + debugfs_remove_recursive(pvt->dbgfs_dir); + pvt->dbgfs_dir = NULL; +} + +static int pvt_ts_dbgfs_create(struct pvt_device *pvt, struct device *dev) +{ + pvt->dbgfs_dir = debugfs_create_dir(dev_name(dev), NULL); + + debugfs_create_u32("ts_coeff_h", 0644, pvt->dbgfs_dir, + &pvt->ts_coeff.h); + debugfs_create_u32("ts_coeff_g", 0644, pvt->dbgfs_dir, + &pvt->ts_coeff.g); + debugfs_create_u32("ts_coeff_cal5", 0644, pvt->dbgfs_dir, + &pvt->ts_coeff.cal5); + debugfs_create_file("ts_coeff_j", 0644, pvt->dbgfs_dir, pvt, + &pvt_ts_coeff_j_fops); + + return devm_add_action_or_reset(dev, devm_pvt_ts_dbgfs_remove, pvt); +} + static umode_t pvt_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr, int channel) { @@ -813,6 +873,8 @@ static int mr75203_probe(struct platform_device *pdev) memset32(temp_config, HWMON_T_INPUT, ts_num); pvt_temp.config = temp_config; pvt_info[index++] = &pvt_temp; + + pvt_ts_dbgfs_create(pvt, dev); } if (pd_num) { -- 2.37.1