Hi Geert,
Thank you for the patch.
On Fri, Oct 18, 2024 at 09:45:52AM +0200, Geert Uytterhoeven wrote:
> Each bridge instance creates up to four auxiliary devices with different
> names. However, their IDs are always zero, causing duplicate filename
> errors when a system has multiple bridges:
>
> sysfs: cannot create duplicate filename '/bus/auxiliary/devices/ti_sn65dsi86.gpio.0'
>
> Fix this by using a unique instance ID per bridge instance.
Isn't this something that should be handled by the AUX core ? The code
below would otherwise need to be duplicated by all drivers, which seems
a burden we should avoid.
> Fixes: bf73537f411b0d4f ("drm/bridge: ti-sn65dsi86: Break GPIO and MIPI-to-eDP bridge into sub-drivers")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> /sys/bus/auxiliary/devices
> ├── ti_sn65dsi86.gpio.0
> ├── ti_sn65dsi86.pwm.0
> ├── ti_sn65dsi86.aux.0
> ├── ti_sn65dsi86.bridge.0
> ├── ti_sn65dsi86.gpio.1
> ├── ti_sn65dsi86.pwm.1
> ├── ti_sn65dsi86.aux.1
> └── ti_sn65dsi86.bridge.1
> ---
> drivers/gpu/drm/bridge/ti-sn65dsi86.c | 24 ++++++++++++++++++++++++
> 1 file changed, 24 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> index 9e31f750fd889745..8f6ac48aefdb70b3 100644
> --- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> +++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
> @@ -13,6 +13,7 @@
> #include <linux/gpio/consumer.h>
> #include <linux/gpio/driver.h>
> #include <linux/i2c.h>
> +#include <linux/idr.h>
> #include <linux/iopoll.h>
> #include <linux/module.h>
> #include <linux/of_graph.h>
> @@ -168,6 +169,7 @@
> * @pwm_enabled: Used to track if the PWM signal is currently enabled.
> * @pwm_pin_busy: Track if GPIO4 is currently requested for GPIO or PWM.
> * @pwm_refclk_freq: Cache for the reference clock input to the PWM.
> + * @id: Unique instance ID
> */
> struct ti_sn65dsi86 {
> struct auxiliary_device *bridge_aux;
> @@ -202,8 +204,11 @@ struct ti_sn65dsi86 {
> atomic_t pwm_pin_busy;
> #endif
> unsigned int pwm_refclk_freq;
> + int id;
> };
>
> +static DEFINE_IDA(ti_sn65dsi86_ida);
> +
> static const struct regmap_range ti_sn65dsi86_volatile_ranges[] = {
> { .range_min = 0, .range_max = 0xFF },
> };
> @@ -488,6 +493,7 @@ static int ti_sn65dsi86_add_aux_device(struct ti_sn65dsi86 *pdata,
> return -ENOMEM;
>
> aux->name = name;
> + aux->id = pdata->id;
> aux->dev.parent = dev;
> aux->dev.release = ti_sn65dsi86_aux_device_release;
> device_set_of_node_from_dev(&aux->dev, dev);
> @@ -1889,6 +1895,13 @@ static int ti_sn65dsi86_parse_regulators(struct ti_sn65dsi86 *pdata)
> pdata->supplies);
> }
>
> +static void ti_sn65dsi86_devm_ida_free(void *data)
> +{
> + struct ti_sn65dsi86 *pdata = data;
> +
> + ida_free(&ti_sn65dsi86_ida, pdata->id);
> +}
> +
> static int ti_sn65dsi86_probe(struct i2c_client *client)
> {
> struct device *dev = &client->dev;
> @@ -1903,6 +1916,17 @@ static int ti_sn65dsi86_probe(struct i2c_client *client)
> pdata = devm_kzalloc(dev, sizeof(struct ti_sn65dsi86), GFP_KERNEL);
> if (!pdata)
> return -ENOMEM;
> +
> + ret = ida_alloc(&ti_sn65dsi86_ida, GFP_KERNEL);
> + if (ret < 0)
> + return ret;
> +
> + pdata->id = ret;
> +
> + ret = devm_add_action_or_reset(dev, ti_sn65dsi86_devm_ida_free, pdata);
> + if (ret)
> + return ret;
> +
> dev_set_drvdata(dev, pdata);
> pdata->dev = dev;
>
--
Regards,
Laurent Pinchart
