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

From: Andy Shevchenko
Date: Mon Feb 15 2016 - 10:13:33 EST


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@xxxxxxxxxxxxxxx>

>
> Cc: Lee Jones <lee.jones@xxxxxxxxxx>
> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> ---
> Âdrivers/mfd/intel_quark_i2c_gpio.c | 26 +++++++++-----------------
> Â1 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 @@
> Â/* The Quark I2C controller source clock */
> Â#define INTEL_QUARK_I2C_CLK_HZ 33000000
> Â
> -#define INTEL_QUARK_I2C_NCLK 1
> -
> Âstruct intel_quark_mfd {
> Â struct pci_dev *pdev;
> Â struct clk *i2c_clk;
> @@ -128,30 +126,24 @@ MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
> Âstatic int intel_quark_register_i2c_clk(struct intel_quark_mfd
> *quark_mfd)
> Â{
> Â struct pci_dev *pdev = quark_mfd->pdev;
> - struct clk_lookup *i2c_clk_lookup;
> Â struct clk *i2c_clk;
> - int ret;
> -
> - i2c_clk_lookup = devm_kcalloc(&pdev->dev,
> INTEL_QUARK_I2C_NCLK,
> - ÂÂÂÂÂÂsizeof(*i2c_clk_lookup),
> GFP_KERNEL);
> - if (!i2c_clk_lookup)
> - return -ENOMEM;
> -
> - i2c_clk_lookup[0].dev_id = INTEL_QUARK_I2C_CONTROLLER_CLK;
> Â
> Â i2c_clk = clk_register_fixed_rate(&pdev->dev,
> Â ÂÂINTEL_QUARK_I2C_CONTROLLER
> _CLK, NULL,
> Â ÂÂCLK_IS_ROOT,
> INTEL_QUARK_I2C_CLK_HZ);
> + if (IS_ERR(i2c_clk))
> + return PTR_ERR(i2c_clk);
> Â
> - quark_mfd->i2c_clk_lookup = i2c_clk_lookup;
> Â quark_mfd->i2c_clk = i2c_clk;
> + quark_mfd->i2c_clk_lookup = clkdev_create(i2c_clk, NULL,
> + INTEL_QUARK_I2C_CONT
> ROLLER_CLK);
> Â
> - ret = clk_register_clkdevs(i2c_clk, i2c_clk_lookup,
> - ÂÂÂINTEL_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;
> + }
> Â
> - return ret;
> + return 0;
> Â}
> Â
> Âstatic void intel_quark_unregister_i2c_clk(struct pci_dev *pdev)

--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy