[PATCH v2 08/13] platform/x86: i2c-multi-instantiate: Count I2cSerialBus() resources

Andy Shevchenko
2018-11-26T15:08:53Z

Instead of relying on hard coded and thus expected number of I2C clients,
count the real amount provided by firmware.

This allows to support non-fixed amount of the slaves.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
---
drivers/platform/x86/i2c-multi-instantiate.c | 41 ++++++++++++++++++--
1 file changed, 37 insertions(+), 4 deletions(-)

diff --git a/drivers/platform/x86/i2c-multi-instantiate.c b/drivers/platform/x86/i2c-multi-instantiate.c
index 16a0eabe1e31..2a405867bbc6 100644
--- a/drivers/platform/x86/i2c-multi-instantiate.c
+++ b/drivers/platform/x86/i2c-multi-instantiate.c
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
+#include <linux/types.h>

struct i2c_inst_data {
const char *type;
@@ -23,6 +24,31 @@ struct i2c_multi_inst_data {
struct i2c_client *clients[0];
};

+static int i2c_multi_inst_count(struct acpi_resource *ares, void *data)
+{
+ struct acpi_resource_i2c_serialbus *sb;
+ int *count = data;
+
+ if (i2c_acpi_get_i2c_resource(ares, &sb))
+ *count = *count + 1;
+
+ return 1;
+}
+
+static int i2c_multi_inst_count_resources(struct acpi_device *adev)
+{
+ LIST_HEAD(r);
+ int count = 0;
+ int ret;
+
+ ret = acpi_dev_get_resources(adev, &r, i2c_multi_inst_count, &count);
+ if (ret < 0)
+ return ret;
+
+ acpi_dev_free_resource_list(&r);
+ return count;
+}
+
static int i2c_multi_inst_probe(struct platform_device *pdev)
{
struct i2c_multi_inst_data *multi;
@@ -44,17 +70,19 @@ static int i2c_multi_inst_probe(struct platform_device *pdev)
adev = ACPI_COMPANION(dev);

/* Count number of clients to instantiate */
- for (i = 0; inst_data[i].type; i++) {}
+ ret = i2c_multi_inst_count_resources(adev);
+ if (ret < 0)
+ return ret;

multi = devm_kmalloc(dev,
- offsetof(struct i2c_multi_inst_data, clients[i]),
+ offsetof(struct i2c_multi_inst_data, clients[ret]),
GFP_KERNEL);
if (!multi)
return -ENOMEM;

- multi->num_clients = i;
+ multi->num_clients = ret;

- for (i = 0; i < multi->num_clients; i++) {
+ for (i = 0; i < multi->num_clients && inst_data[i].type; i++) {
memset(&board_info, 0, sizeof(board_info));
strlcpy(board_info.type, inst_data[i].type, I2C_NAME_SIZE);
snprintf(name, sizeof(name), "%s-%s", match->id,
@@ -83,6 +111,11 @@ static int i2c_multi_inst_probe(struct platform_device *pdev)
goto error;
}
}
+ if (i < multi->num_clients) {
+ dev_err(dev, "Error finding driver, idx %d\n", i);
+ ret = -ENODEV;
+ goto error;
+ }

platform_set_drvdata(pdev, multi);
return 0;
--
2.19.1