by Stefan Wahren

[permalink] [raw]

Subject: Re: [PATCH v9 1/5] mfd: mxs-lradc: Add support for mxs-lradc MFD

Hi Ksenija,

> Ksenija Stanojevic <[email protected]> hat am 2. November 2016 um
> 08:38 geschrieben:
>
>
> Add core files for low resolution analog-to-digital converter (mxs-lradc)
> MFD driver.
>
> Signed-off-by: Ksenija Stanojevic <[email protected]>
> ---
> Changes in v9:
> - improve commit message.
>
> Changes in v8:
> - rebase onto 4.9-rc1
>
> Changes in v7:
> - define macros ADC_CELL and TSC_CELL
> - remove one cell and dynamically set them in the switch()
> - fail in the touchscreen driver instead of mfd driver if
> hardware doesn't contain a touchscreen
>
> Changes in v6:
> - update copyright
> - add kernel-doc header for struct mxs-lradc
> - add error message
> - change EINVAL to ENODEV
> - use PLATFORM_DEVID_NONE instead -1
> - cosmetic fixes
>
> Changes in v5:
> - use DEFINE_RES_MEM
> - don't pass ioreammaped adress to platform cells
> - move comment outside of struct mxs_lradc
> - change type of argument in mxs_lradc_reg_set, mxs_lradc_reg_clear,
> mxs_lradc_reg_wrt (struct mxs_lradc * -> void __iomem *)
>
> Changes in v4:
> - update copyright
> - use DEFINE_RES_IRQ_NAMED
> - remove mxs_lradc_add_device function
> - use struct mfd_cell in static form
> - improve spacing
> - remove unnecessary comment
> - remove platform_get_irq
> - remove touch_ret and use ret instead
> - rename use_touchscreen to touchscreen_wire
> - use goto statements
> - remove irq[13], irq_count and irq_name from struct mxs_lradc
> - remove all defines from inside the struct definition
>
> Changes in v3:
> - add note to commit message
> - move switch statement into if(touch_ret == 0) branch
> - add MODULE_AUTHOR
>
> Changes in v2:
> - do not change spacing in Kconfig
> - make struct mfd_cell part of struct mxs_lradc
> - use switch instead of if in mxs_lradc_irq_mask
> - use only necessary header files in mxs_lradc.h
> - use devm_mfd_add_device
> - use separate function to register mfd device
> - change licence to GPL
> - add copyright
>
> drivers/mfd/Kconfig | 17 +++
> drivers/mfd/Makefile | 1 +
> drivers/mfd/mxs-lradc.c | 249
> ++++++++++++++++++++++++++++++++++++++++++
> include/linux/mfd/mxs-lradc.h | 203 ++++++++++++++++++++++++++++++++++
> 4 files changed, 470 insertions(+)
> create mode 100644 drivers/mfd/mxs-lradc.c
> create mode 100644 include/linux/mfd/mxs-lradc.h
>
> ...
> diff --git a/drivers/mfd/mxs-lradc.c b/drivers/mfd/mxs-lradc.c
> new file mode 100644
> index 0000000..ffc8f2e
> --- /dev/null
> +++ b/drivers/mfd/mxs-lradc.c
> @@ -0,0 +1,249 @@
> ...
> +
> +static const struct of_device_id mxs_lradc_dt_ids[] = {
> + { .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
> + { .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
> +
> +static int mxs_lradc_probe(struct platform_device *pdev)
> +{
> + const struct of_device_id *of_id;
> + struct device *dev = &pdev->dev;
> + struct device_node *node = dev->of_node;
> + struct mxs_lradc *lradc;
> + struct mfd_cell *cells = mxs_cells;
> + int ret = 0;
> + u32 ts_wires = 0;
> +
> + lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
> + if (!lradc)
> + return -ENOMEM;
> +
> + of_id = of_match_device(mxs_lradc_dt_ids, &pdev->dev);

since you already plan to make a V10, please add a NULL check here.
So we can avoid a possible NULL pointer dereference in the following line.

Thanks
Stefan

> + lradc->soc = (enum mxs_lradc_id)of_id->data;
> +
> + lradc->clk = devm_clk_get(&pdev->dev, NULL);
> + if (IS_ERR(lradc->clk)) {
> + dev_err(dev, "Failed to get the delay unit clock\n");
> + return PTR_ERR(lradc->clk);
> + }
> +
> + ret = clk_prepare_enable(lradc->clk);
> + if (ret) {
> + dev_err(dev, "Failed to enable the delay unit clock\n");
> + return ret;
> + }
> +

2016-11-15 19:55:41

by Ksenija Stanojevic

[permalink] [raw]

Subject: Re: [PATCH v9 1/5] mfd: mxs-lradc: Add support for mxs-lradc MFD

On Tue, Nov 15, 2016 at 8:33 PM, Stefan Wahren <[email protected]> wrote:
> Hi Ksenija,
>
>> Ksenija Stanojevic <[email protected]> hat am 2. November 2016 um
>> 08:38 geschrieben:
>>
>>
>> Add core files for low resolution analog-to-digital converter (mxs-lradc)
>> MFD driver.
>>
>> Signed-off-by: Ksenija Stanojevic <[email protected]>
>> ---
>> Changes in v9:
>> - improve commit message.
>>
>> Changes in v8:
>> - rebase onto 4.9-rc1
>>
>> Changes in v7:
>> - define macros ADC_CELL and TSC_CELL
>> - remove one cell and dynamically set them in the switch()
>> - fail in the touchscreen driver instead of mfd driver if
>> hardware doesn't contain a touchscreen
>>
>> Changes in v6:
>> - update copyright
>> - add kernel-doc header for struct mxs-lradc
>> - add error message
>> - change EINVAL to ENODEV
>> - use PLATFORM_DEVID_NONE instead -1
>> - cosmetic fixes
>>
>> Changes in v5:
>> - use DEFINE_RES_MEM
>> - don't pass ioreammaped adress to platform cells
>> - move comment outside of struct mxs_lradc
>> - change type of argument in mxs_lradc_reg_set, mxs_lradc_reg_clear,
>> mxs_lradc_reg_wrt (struct mxs_lradc * -> void __iomem *)
>>
>> Changes in v4:
>> - update copyright
>> - use DEFINE_RES_IRQ_NAMED
>> - remove mxs_lradc_add_device function
>> - use struct mfd_cell in static form
>> - improve spacing
>> - remove unnecessary comment
>> - remove platform_get_irq
>> - remove touch_ret and use ret instead
>> - rename use_touchscreen to touchscreen_wire
>> - use goto statements
>> - remove irq[13], irq_count and irq_name from struct mxs_lradc
>> - remove all defines from inside the struct definition
>>
>> Changes in v3:
>> - add note to commit message
>> - move switch statement into if(touch_ret == 0) branch
>> - add MODULE_AUTHOR
>>
>> Changes in v2:
>> - do not change spacing in Kconfig
>> - make struct mfd_cell part of struct mxs_lradc
>> - use switch instead of if in mxs_lradc_irq_mask
>> - use only necessary header files in mxs_lradc.h
>> - use devm_mfd_add_device
>> - use separate function to register mfd device
>> - change licence to GPL
>> - add copyright
>>
>> drivers/mfd/Kconfig | 17 +++
>> drivers/mfd/Makefile | 1 +
>> drivers/mfd/mxs-lradc.c | 249
>> ++++++++++++++++++++++++++++++++++++++++++
>> include/linux/mfd/mxs-lradc.h | 203 ++++++++++++++++++++++++++++++++++
>> 4 files changed, 470 insertions(+)
>> create mode 100644 drivers/mfd/mxs-lradc.c
>> create mode 100644 include/linux/mfd/mxs-lradc.h
>>
>> ...
>> diff --git a/drivers/mfd/mxs-lradc.c b/drivers/mfd/mxs-lradc.c
>> new file mode 100644
>> index 0000000..ffc8f2e
>> --- /dev/null
>> +++ b/drivers/mfd/mxs-lradc.c
>> @@ -0,0 +1,249 @@
>> ...
>> +
>> +static const struct of_device_id mxs_lradc_dt_ids[] = {
>> + { .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
>> + { .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
>> + { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
>> +
>> +static int mxs_lradc_probe(struct platform_device *pdev)
>> +{
>> + const struct of_device_id *of_id;
>> + struct device *dev = &pdev->dev;
>> + struct device_node *node = dev->of_node;
>> + struct mxs_lradc *lradc;
>> + struct mfd_cell *cells = mxs_cells;
>> + int ret = 0;
>> + u32 ts_wires = 0;
>> +
>> + lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
>> + if (!lradc)
>> + return -ENOMEM;
>> +
>> + of_id = of_match_device(mxs_lradc_dt_ids, &pdev->dev);
>
> since you already plan to make a V10, please add a NULL check here.
> So we can avoid a possible NULL pointer dereference in the following line.

Ok. I will.

Thanks,
Ksenija

>
>> + lradc->soc = (enum mxs_lradc_id)of_id->data;
>> +
>> + lradc->clk = devm_clk_get(&pdev->dev, NULL);
>> + if (IS_ERR(lradc->clk)) {
>> + dev_err(dev, "Failed to get the delay unit clock\n");
>> + return PTR_ERR(lradc->clk);
>> + }
>> +
>> + ret = clk_prepare_enable(lradc->clk);
>> + if (ret) {
>> + dev_err(dev, "Failed to enable the delay unit clock\n");
>> + return ret;
>> + }
>> +