Re: [PATCH 01/14] mfd: intel_quark_i2c_gpio: Use clkdev_create()

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Mon, 2016-02-08 at 17:45 -0800, Stephen Boyd wrote:
> Convert this driver to use clkdev_create() instead of
> clk_register_clkdevs(). The latter API is only used by this driver,
> although this driver only allocates one clk to add anyway.
> Furthermore, this driver allocates the clk_lookup structure with
> devm, but clkdev_drop() will free that structure when passed,
> leading to a double free when this driver is removed. Clean it
> all up and pave the way for the removal of clk_register_clkdevs().

Good one.

I have still in my local tree the fix regarding to this code since I
found an error in the error path (we don't free clk resources). So, I
will re-base it, although it will require to go with two patches
instead of one if we go to stable.

For this one:
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> 
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Cc: Russell King <linux@arm.linux.org.uk>
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> ---
>  drivers/mfd/intel_quark_i2c_gpio.c | 26 +++++++++-----------------
>  1 file changed, 9 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/mfd/intel_quark_i2c_gpio.c
> b/drivers/mfd/intel_quark_i2c_gpio.c
> index 042137465300..bdc5e27222c0 100644
> --- a/drivers/mfd/intel_quark_i2c_gpio.c
> +++ b/drivers/mfd/intel_quark_i2c_gpio.c
> @@ -52,8 +52,6 @@
>  /* The Quark I2C controller source clock */
>  #define INTEL_QUARK_I2C_CLK_HZ	33000000
>  
> -#define INTEL_QUARK_I2C_NCLK	1
> -
>  struct intel_quark_mfd {
>  	struct pci_dev		*pdev;
>  	struct clk		*i2c_clk;
> @@ -128,30 +126,24 @@ MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
>  static int intel_quark_register_i2c_clk(struct intel_quark_mfd
> *quark_mfd)
>  {
>  	struct pci_dev *pdev = quark_mfd->pdev;
> -	struct clk_lookup *i2c_clk_lookup;
>  	struct clk *i2c_clk;
> -	int ret;
> -
> -	i2c_clk_lookup = devm_kcalloc(&pdev->dev,
> INTEL_QUARK_I2C_NCLK,
> -				      sizeof(*i2c_clk_lookup),
> GFP_KERNEL);
> -	if (!i2c_clk_lookup)
> -		return -ENOMEM;
> -
> -	i2c_clk_lookup[0].dev_id = INTEL_QUARK_I2C_CONTROLLER_CLK;
>  
>  	i2c_clk = clk_register_fixed_rate(&pdev->dev,
>  					  INTEL_QUARK_I2C_CONTROLLER
> _CLK, NULL,
>  					  CLK_IS_ROOT,
> INTEL_QUARK_I2C_CLK_HZ);
> +	if (IS_ERR(i2c_clk))
> +		return PTR_ERR(i2c_clk);
>  
> -	quark_mfd->i2c_clk_lookup = i2c_clk_lookup;
>  	quark_mfd->i2c_clk = i2c_clk;
> +	quark_mfd->i2c_clk_lookup = clkdev_create(i2c_clk, NULL,
> +						INTEL_QUARK_I2C_CONT
> ROLLER_CLK);
>  
> -	ret = clk_register_clkdevs(i2c_clk, i2c_clk_lookup,
> -				   INTEL_QUARK_I2C_NCLK);
> -	if (ret)
> -		dev_err(&pdev->dev, "Fixed clk register failed:
> %d\n", ret);
> +	if (!quark_mfd->i2c_clk_lookup) {
> +		dev_err(&pdev->dev, "Fixed clk register failed\n");
> +		return -ENOMEM;
> +	}
>  
> -	return ret;
> +	return 0;
>  }
>  
>  static void intel_quark_unregister_i2c_clk(struct pci_dev *pdev)

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy