Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
Changes in v2:
- Factor out the parsing into a separate helper function
---
drivers/iio/light/cm32181.c | 101 ++++++++++++++++++++++++++++++++++++
1 file changed, 101 insertions(+)
diff --git a/drivers/iio/light/cm32181.c b/drivers/iio/light/cm32181.c
index cae2264e4336..d8b128286527 100644
--- a/drivers/iio/light/cm32181.c
+++ b/drivers/iio/light/cm32181.c
@@ -4,6 +4,7 @@
* Author: Kevin Tsai <ktsai@xxxxxxxxxxxxxxxx>
*/
+#include <linux/acpi.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/i2c.h>
@@ -53,6 +54,15 @@
#define SMBUS_ALERT_RESPONSE_ADDRESS 0x0c
+/* CPM0 Index 0: device-id (3218 or 32181), 1: Unknown, 2: init_regs_bitmap */
+#define CPM0_REGS_BITMAP 2
+#define CPM0_HEADER_SIZE 3
+
+/* CPM1 Index 0: lux_per_bit, 1: calibscale, 2: resolution (100000) */
+#define CPM1_LUX_PER_BIT 0
+#define CPM1_CALIBSCALE 1
+#define CPM1_SIZE 3
+
/* CM3218 Family */
static const int cm3218_als_it_bits[] = { 0, 1, 2, 3 };
static const int cm3218_als_it_values[] = { 100000, 200000, 400000, 800000 };
@@ -65,6 +75,7 @@ static const int cm32181_als_it_values[] = {
struct cm32181_chip {
struct i2c_client *client;
+ struct device *dev;
struct mutex lock;
u16 conf_regs[CM32181_CONF_REG_NUM];
unsigned long init_regs_bitmap;
@@ -76,6 +87,92 @@ struct cm32181_chip {
const int *als_it_values;
};
+static int cm32181_read_als_it(struct cm32181_chip *cm32181, int *val2);
+
+#ifdef CONFIG_ACPI
+/**
+ * cm32181_acpi_get_cpm() - Get CPM object from ACPI
+ * @client pointer of struct i2c_client.
+ * @obj_name pointer of ACPI object name.
+ * @count maximum size of return array.
+ * @vals pointer of array for return elements.
+ *
+ * Convert ACPI CPM table to array.
+ *
+ * Return: -ENODEV for fail. Otherwise is number of elements.
+ */
+static int cm32181_acpi_get_cpm(struct device *dev, char *obj_name,
+ u64 *values, int count)
+{
+ struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *cpm, *elem;
+ acpi_handle handle;
+ acpi_status status;
+ int i;
+
+ handle = ACPI_HANDLE(dev);
+ if (!handle)
+ return -ENODEV;
+
+ status = acpi_evaluate_object(handle, obj_name, NULL, &buffer);
+ if (ACPI_FAILURE(status)) {
+ dev_err(dev, "object %s not found\n", obj_name);
+ return -ENODEV;
+ }
+
+ cpm = buffer.pointer;
+ if (cpm->package.count > count)
+ dev_warn(dev, "%s table contains %d values, only using first %d values\n",
+ obj_name, cpm->package.count, count);
+
+ count = min_t(int, cpm->package.count, count);
+ for (i = 0; i < count; i++) {
+ elem = &(cpm->package.elements[i]);
+ values[i] = elem->integer.value;
+ }
+
+ kfree(buffer.pointer);
+
+ return count;
+}
+
+static void cm32181_acpi_parse_cpm_tables(struct cm32181_chip *cm32181)
+{
+ u64 vals[CPM0_HEADER_SIZE + CM32181_CONF_REG_NUM];
+ struct device *dev = cm32181->dev;
+ int i, count;
+
+ count = cm32181_acpi_get_cpm(dev, "CPM0", vals, ARRAY_SIZE(vals));
+ if (count <= CPM0_HEADER_SIZE)
+ return;
+
+ count -= CPM0_HEADER_SIZE;
+
+ cm32181->init_regs_bitmap = vals[CPM0_REGS_BITMAP];
+ cm32181->init_regs_bitmap &= GENMASK(count - 1, 0);
+ for_each_set_bit(i, &cm32181->init_regs_bitmap, count)
+ cm32181->conf_regs[i] = vals[CPM0_HEADER_SIZE + i];
+
+ count = cm32181_acpi_get_cpm(dev, "CPM1", vals, ARRAY_SIZE(vals));
+ if (count != CPM1_SIZE)
+ return;
+
+ cm32181->lux_per_bit = vals[CPM1_LUX_PER_BIT];
+
+ /* Check for uncalibrated devices */
+ if (vals[CPM1_CALIBSCALE] == CM32181_CALIBSCALE_DEFAULT)
+ return;
+
+ cm32181->calibscale = vals[CPM1_CALIBSCALE];
+ /* CPM1 lux_per_bit is for the current it value */
+ cm32181_read_als_it(cm32181, &cm32181->lux_per_bit_base_it);
+}
+#else
+static void cm32181_acpi_parse_cpm_tables(struct cm32181_chip *cm32181)
+{
+}
+#endif /* CONFIG_ACPI */
+
/**
* cm32181_reg_init() - Initialize CM32181 registers
* @cm32181: pointer of struct cm32181.
@@ -119,6 +216,9 @@ static int cm32181_reg_init(struct cm32181_chip *cm32181)
cm32181->lux_per_bit = CM32181_LUX_PER_BIT;
cm32181->lux_per_bit_base_it = CM32181_LUX_PER_BIT_BASE_IT;
+ if (ACPI_HANDLE(cm32181->dev))
+ cm32181_acpi_parse_cpm_tables(cm32181);
+
/* Initialize registers*/
for_each_set_bit(i, &cm32181->init_regs_bitmap, CM32181_CONF_REG_NUM) {
ret = i2c_smbus_write_word_data(client, i,
@@ -361,6 +461,7 @@ static int cm32181_probe(struct i2c_client *client)
cm32181 = iio_priv(indio_dev);
cm32181->client = client;
+ cm32181->dev = dev;
mutex_init(&cm32181->lock);
indio_dev->dev.parent = dev;
