hwmon: (pwm-fan) Convert to use of_property_read_u32_array()

This is a preparatory change to fulfill further conversion
the driver to be OF-independent. The independent code has
no analogue API that can read the value by index in the device
property array.

Suggested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20240404191323.3547465-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index b67bc9e833c01e1db8d2311c39334866fe44e638..bf902610cd0794305ff7f5a6d8ab5c842198ae2b 100644 (file)
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -25,7 +25,6 @@ struct pwm_fan_tach {
        int irq;
        atomic_t pulses;
        unsigned int rpm;
-       u8 pulses_per_revolution;
 };
 
 enum pwm_fan_enable_mode {
@@ -48,6 +47,7 @@ struct pwm_fan_ctx {
 
        int tach_count;
        struct pwm_fan_tach *tachs;
+       u32 *pulses_per_revolution;
        ktime_t sample_start;
        struct timer_list rpm_timer;
 
@@ -85,7 +85,7 @@ static void sample_timer(struct timer_list *t)
                        pulses = atomic_read(&tach->pulses);
                        atomic_sub(pulses, &tach->pulses);
                        tach->rpm = (unsigned int)(pulses * 1000 * 60) /
-                               (tach->pulses_per_revolution * delta);
+                               (ctx->pulses_per_revolution[i] * delta);
                }
 
                ctx->sample_start = ktime_get();
@@ -562,6 +562,20 @@ static int pwm_fan_probe(struct platform_device *pdev)
                if (!fan_channel_config)
                        return -ENOMEM;
                ctx->fan_channel.config = fan_channel_config;
+
+               ctx->pulses_per_revolution = devm_kmalloc_array(dev,
+                                                               ctx->tach_count,
+                                                               sizeof(*ctx->pulses_per_revolution),
+                                                               GFP_KERNEL);
+               if (!ctx->pulses_per_revolution)
+                       return -ENOMEM;
+
+               /* Setup default pulses per revolution */
+               for (i = 0; i < ctx->tach_count; i++)
+                       ctx->pulses_per_revolution[i] = 2;
+
+               of_property_read_u32_array(dev->of_node, "pulses-per-revolution",
+                                          ctx->pulses_per_revolution, ctx->tach_count);
        }
 
        channels = devm_kcalloc(dev, channel_count + 1,
@@ -573,7 +587,6 @@ static int pwm_fan_probe(struct platform_device *pdev)
 
        for (i = 0; i < ctx->tach_count; i++) {
                struct pwm_fan_tach *tach = &ctx->tachs[i];
-               u32 ppr = 2;
 
                tach->irq = platform_get_irq(pdev, i);
                if (tach->irq == -EPROBE_DEFER)
@@ -589,12 +602,7 @@ static int pwm_fan_probe(struct platform_device *pdev)
                        }
                }
 
-               of_property_read_u32_index(dev->of_node,
-                                          "pulses-per-revolution",
-                                          i,
-                                          &ppr);
-               tach->pulses_per_revolution = ppr;
-               if (!tach->pulses_per_revolution) {
+               if (!ctx->pulses_per_revolution[i]) {
                        dev_err(dev, "pulses-per-revolution can't be zero.\n");
                        return -EINVAL;
                }
@@ -602,7 +610,7 @@ static int pwm_fan_probe(struct platform_device *pdev)
                fan_channel_config[i] = HWMON_F_INPUT;
 
                dev_dbg(dev, "tach%d: irq=%d, pulses_per_revolution=%d\n",
-                       i, tach->irq, tach->pulses_per_revolution);
+                       i, tach->irq, ctx->pulses_per_revolution[i]);
        }
 
        if (ctx->tach_count > 0) {