On Mon, Jul 28, 2014 at 03:19:43PM -0300, Fabio Estevam wrote:
Hi Nicolin,
On Mon, Jul 28, 2014 at 9:22 AM, Mark Brown broonie@kernel.org wrote:
On Mon, Jul 28, 2014 at 07:41:58PM +0800, Nicolin Chen wrote:
pdata->mclk = devm_clk_get(&i2c->dev, NULL);This is broken for deferred probe.
Hi Mark,
Sorry. I don't get why deferred probe would be broken by this. And I just took a test by adding this:
[...] @@ -3545,10 +3545,11 @@ static int wm8962_set_pdata_from_of(struct i2c_client *i2c, }
+bool letstry = true; static int wm8962_i2c_probe(struct i2c_client *i2c, const struct i2c_device_id *id) @@ -3573,10 +3574,15 @@ static int wm8962_i2c_probe(struct i2c_client *i2c, ret = wm8962_set_pdata_from_of(i2c, &wm8962->pdata); if (ret != 0) return ret; } + if (letstry) { + letstry = false; + return -EPROBE_DEFER; + } /* Mark the mclk pointer to NULL if no mclk assigned */ if (IS_ERR(wm8962->pdata.mclk)) wm8962->pdata.mclk = NULL; [...]
And it still works for me with a deferred probe:
[] i2c 0-001a: Driver wm8962 requests probe deferral []... []wm8962 0-001a: customer id 0 revision D []input: WM8962 Beep Generator as /devices/soc0/soc/2100000...... []fsl-asoc-card sound: wm8962 <-> 202c000.ssi mapping ok
You can take a look at sgtl5000 to see how we handle deferred probe in devm_clk_get().
Hi Fabio,
Thank you for the hint.
But actually, unlike sgtl5000, this patch doesn't error out for IS_ERR(mclk) case.
There might be a machine driver that has already got and enabled the clock while getting the clock from other way or other DT node rather than WM8962's.
Thank you. Nicolin