Re: [PATCH v2] iio: stm32-adc: remove usage of iio_priv_to_dev() helper
From: Fabrice Gasnier
Date: Mon May 25 2020 - 12:28:01 EST
On 5/25/20 11:07 AM, Alexandru Ardelean wrote:
> We may want to get rid of the iio_priv_to_dev() helper. The reason is that
> we will hide some of the members of the iio_dev structure (to prevent
> drivers from accessing them directly), and that will also mean hiding the
> implementation of the iio_priv_to_dev() helper inside the IIO core.
>
> Hiding the implementation of iio_priv_to_dev() implies that some fast-paths
> may not be fast anymore, so a general idea is to try to get rid of the
> iio_priv_to_dev() altogether.
> The iio_priv() helper won't be affected by the rework, as the iio_dev
> struct will keep a reference to the private information.
>
> For this driver, not using iio_priv_to_dev(), means reworking some paths to
> pass the iio device and using iio_priv() to access the private information.
>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> ---
> drivers/iio/adc/stm32-adc.c | 108 +++++++++++++++++++-----------------
> 1 file changed, 58 insertions(+), 50 deletions(-)
>
> diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
> index ae622ee6d08c..9428c5c22712 100644
> --- a/drivers/iio/adc/stm32-adc.c
> +++ b/drivers/iio/adc/stm32-adc.c
> @@ -162,10 +162,10 @@ struct stm32_adc_cfg {
> struct stm32_adc_trig_info *trigs;
> bool clk_required;
> bool has_vregready;
> - int (*prepare)(struct stm32_adc *);
> - void (*start_conv)(struct stm32_adc *, bool dma);
> - void (*stop_conv)(struct stm32_adc *);
> - void (*unprepare)(struct stm32_adc *);
> + int (*prepare)(struct iio_dev *);
> + void (*start_conv)(struct iio_dev *, bool dma);
> + void (*stop_conv)(struct iio_dev *);
> + void (*unprepare)(struct iio_dev *);
> const unsigned int *smp_cycles;
> };
>
> @@ -538,10 +538,11 @@ static void stm32_adc_set_res(struct stm32_adc *adc)
>
> static int stm32_adc_hw_stop(struct device *dev)
> {
> - struct stm32_adc *adc = dev_get_drvdata(dev);
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct stm32_adc *adc = iio_priv(indio_dev);
>
> if (adc->cfg->unprepare)
> - adc->cfg->unprepare(adc);
> + adc->cfg->unprepare(indio_dev);
>
> if (adc->clk)
> clk_disable_unprepare(adc->clk);
> @@ -551,7 +552,8 @@ static int stm32_adc_hw_stop(struct device *dev)
>
> static int stm32_adc_hw_start(struct device *dev)
> {
> - struct stm32_adc *adc = dev_get_drvdata(dev);
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int ret;
>
> if (adc->clk) {
> @@ -563,7 +565,7 @@ static int stm32_adc_hw_start(struct device *dev)
> stm32_adc_set_res(adc);
>
> if (adc->cfg->prepare) {
> - ret = adc->cfg->prepare(adc);
> + ret = adc->cfg->prepare(indio_dev);
> if (ret)
> goto err_clk_dis;
> }
> @@ -587,8 +589,10 @@ static int stm32_adc_hw_start(struct device *dev)
> * conversions, in IIO buffer modes. Otherwise, use ADC interrupt with direct
> * DR read instead (e.g. read_raw, or triggered buffer mode without DMA).
> */
> -static void stm32f4_adc_start_conv(struct stm32_adc *adc, bool dma)
> +static void stm32f4_adc_start_conv(struct iio_dev *indio_dev, bool dma)
Hi Alexandru,
I've tested your patch. I've no objection, but found few build warnings
(some of these routines have kernel-doc style).
Building with W=1 makes warnings appear, like:
drivers/iio/adc/stm32-adc.c:593: warning: Function parameter or member
'indio_dev' not described in 'stm32f4_adc_start_conv'
drivers/iio/adc/stm32-adc.c:593: warning: Excess function parameter
'adc' description in 'stm32f4_adc_start_conv'
...
Could you update routine's doc as well ?
e.g. something like:
- * @adc: stm32 adc instance
+ * @indio_dev: IIO device
> {
> + struct stm32_adc *adc = iio_priv(indio_dev);
> +
> stm32_adc_set_bits(adc, STM32F4_ADC_CR1, STM32F4_SCAN);
>
> if (dma)
> @@ -605,8 +609,10 @@ static void stm32f4_adc_start_conv(struct stm32_adc *adc, bool dma)
> stm32_adc_set_bits(adc, STM32F4_ADC_CR2, STM32F4_SWSTART);
> }
>
> -static void stm32f4_adc_stop_conv(struct stm32_adc *adc)
> +static void stm32f4_adc_stop_conv(struct iio_dev *indio_dev)
> {
> + struct stm32_adc *adc = iio_priv(indio_dev);
> +
> stm32_adc_clr_bits(adc, STM32F4_ADC_CR2, STM32F4_EXTEN_MASK);
> stm32_adc_clr_bits(adc, STM32F4_ADC_SR, STM32F4_STRT);
>
> @@ -615,8 +621,9 @@ static void stm32f4_adc_stop_conv(struct stm32_adc *adc)
> STM32F4_ADON | STM32F4_DMA | STM32F4_DDS);
> }
>
> -static void stm32h7_adc_start_conv(struct stm32_adc *adc, bool dma)
> +static void stm32h7_adc_start_conv(struct iio_dev *indio_dev, bool dma)
> {
> + struct stm32_adc *adc = iio_priv(indio_dev);
> enum stm32h7_adc_dmngt dmngt;
> unsigned long flags;
> u32 val;
> @@ -635,9 +642,9 @@ static void stm32h7_adc_start_conv(struct stm32_adc *adc, bool dma)
> stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADSTART);
> }
>
> -static void stm32h7_adc_stop_conv(struct stm32_adc *adc)
> +static void stm32h7_adc_stop_conv(struct iio_dev *indio_dev)
> {
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int ret;
> u32 val;
>
> @@ -652,9 +659,9 @@ static void stm32h7_adc_stop_conv(struct stm32_adc *adc)
> stm32_adc_clr_bits(adc, STM32H7_ADC_CFGR, STM32H7_DMNGT_MASK);
> }
>
> -static int stm32h7_adc_exit_pwr_down(struct stm32_adc *adc)
> +static int stm32h7_adc_exit_pwr_down(struct iio_dev *indio_dev)
> {
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int ret;
> u32 val;
>
> @@ -690,9 +697,9 @@ static void stm32h7_adc_enter_pwr_down(struct stm32_adc *adc)
> stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_DEEPPWD);
> }
>
> -static int stm32h7_adc_enable(struct stm32_adc *adc)
> +static int stm32h7_adc_enable(struct iio_dev *indio_dev)
> {
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int ret;
> u32 val;
>
> @@ -713,9 +720,9 @@ static int stm32h7_adc_enable(struct stm32_adc *adc)
> return ret;
> }
>
> -static void stm32h7_adc_disable(struct stm32_adc *adc)
> +static void stm32h7_adc_disable(struct iio_dev *indio_dev)
> {
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int ret;
> u32 val;
>
> @@ -733,9 +740,9 @@ static void stm32h7_adc_disable(struct stm32_adc *adc)
> * @adc: stm32 adc instance
> * Note: Must be called once ADC is enabled, so LINCALRDYW[1..6] are writable
> */
> -static int stm32h7_adc_read_selfcalib(struct stm32_adc *adc)
> +static int stm32h7_adc_read_selfcalib(struct iio_dev *indio_dev)
Same here.
> {
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int i, ret;
> u32 lincalrdyw_mask, val;
>
> @@ -777,9 +784,9 @@ static int stm32h7_adc_read_selfcalib(struct stm32_adc *adc)
> * @adc: stm32 adc instance
> * Note: ADC must be enabled, with no on-going conversions.
> */
> -static int stm32h7_adc_restore_selfcalib(struct stm32_adc *adc)
> +static int stm32h7_adc_restore_selfcalib(struct iio_dev *indio_dev)
Same here.
> {
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int i, ret;
> u32 lincalrdyw_mask, val;
>
> @@ -850,9 +857,9 @@ static int stm32h7_adc_restore_selfcalib(struct stm32_adc *adc)
> * @adc: stm32 adc instance
> * Note: Must be called once ADC is out of power down.
> */
> -static int stm32h7_adc_selfcalib(struct stm32_adc *adc)
> +static int stm32h7_adc_selfcalib(struct iio_dev *indio_dev)
Same here
> {
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int ret;
> u32 val;
>
> @@ -912,30 +919,31 @@ static int stm32h7_adc_selfcalib(struct stm32_adc *adc)
> * - Only one input is selected for single ended (e.g. 'vinp')
> * - Two inputs are selected for differential channels (e.g. 'vinp' & 'vinn')
> */
> -static int stm32h7_adc_prepare(struct stm32_adc *adc)
> +static int stm32h7_adc_prepare(struct iio_dev *indio_dev)
Same here.
With the comments updated, you can add my:
Acked-by: Fabrice Gasnier <fabrice.gasnier@xxxxxx>
Thanks for the patch,
Fabrice
> {
> + struct stm32_adc *adc = iio_priv(indio_dev);
> int calib, ret;
>
> - ret = stm32h7_adc_exit_pwr_down(adc);
> + ret = stm32h7_adc_exit_pwr_down(indio_dev);
> if (ret)
> return ret;
>
> - ret = stm32h7_adc_selfcalib(adc);
> + ret = stm32h7_adc_selfcalib(indio_dev);
> if (ret < 0)
> goto pwr_dwn;
> calib = ret;
>
> stm32_adc_writel(adc, STM32H7_ADC_DIFSEL, adc->difsel);
>
> - ret = stm32h7_adc_enable(adc);
> + ret = stm32h7_adc_enable(indio_dev);
> if (ret)
> goto pwr_dwn;
>
> /* Either restore or read calibration result for future reference */
> if (calib)
> - ret = stm32h7_adc_restore_selfcalib(adc);
> + ret = stm32h7_adc_restore_selfcalib(indio_dev);
> else
> - ret = stm32h7_adc_read_selfcalib(adc);
> + ret = stm32h7_adc_read_selfcalib(indio_dev);
> if (ret)
> goto disable;
>
> @@ -944,16 +952,18 @@ static int stm32h7_adc_prepare(struct stm32_adc *adc)
> return 0;
>
> disable:
> - stm32h7_adc_disable(adc);
> + stm32h7_adc_disable(indio_dev);
> pwr_dwn:
> stm32h7_adc_enter_pwr_down(adc);
>
> return ret;
> }
>
> -static void stm32h7_adc_unprepare(struct stm32_adc *adc)
> +static void stm32h7_adc_unprepare(struct iio_dev *indio_dev)
> {
> - stm32h7_adc_disable(adc);
> + struct stm32_adc *adc = iio_priv(indio_dev);
> +
> + stm32h7_adc_disable(indio_dev);
> stm32h7_adc_enter_pwr_down(adc);
> }
>
> @@ -1160,7 +1170,7 @@ static int stm32_adc_single_conv(struct iio_dev *indio_dev,
>
> stm32_adc_conv_irq_enable(adc);
>
> - adc->cfg->start_conv(adc, false);
> + adc->cfg->start_conv(indio_dev, false);
>
> timeout = wait_for_completion_interruptible_timeout(
> &adc->completion, STM32_ADC_TIMEOUT);
> @@ -1173,7 +1183,7 @@ static int stm32_adc_single_conv(struct iio_dev *indio_dev,
> ret = IIO_VAL_INT;
> }
>
> - adc->cfg->stop_conv(adc);
> + adc->cfg->stop_conv(indio_dev);
>
> stm32_adc_conv_irq_disable(adc);
>
> @@ -1227,8 +1237,8 @@ static int stm32_adc_read_raw(struct iio_dev *indio_dev,
>
> static irqreturn_t stm32_adc_threaded_isr(int irq, void *data)
> {
> - struct stm32_adc *adc = data;
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct iio_dev *indio_dev = data;
> + struct stm32_adc *adc = iio_priv(indio_dev);
> const struct stm32_adc_regspec *regs = adc->cfg->regs;
> u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg);
>
> @@ -1240,8 +1250,8 @@ static irqreturn_t stm32_adc_threaded_isr(int irq, void *data)
>
> static irqreturn_t stm32_adc_isr(int irq, void *data)
> {
> - struct stm32_adc *adc = data;
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct iio_dev *indio_dev = data;
> + struct stm32_adc *adc = iio_priv(indio_dev);
> const struct stm32_adc_regspec *regs = adc->cfg->regs;
> u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg);
>
> @@ -1514,7 +1524,7 @@ static int __stm32_adc_buffer_postenable(struct iio_dev *indio_dev)
> if (!adc->dma_chan)
> stm32_adc_conv_irq_enable(adc);
>
> - adc->cfg->start_conv(adc, !!adc->dma_chan);
> + adc->cfg->start_conv(indio_dev, !!adc->dma_chan);
>
> return 0;
>
> @@ -1547,7 +1557,7 @@ static void __stm32_adc_buffer_predisable(struct iio_dev *indio_dev)
> struct stm32_adc *adc = iio_priv(indio_dev);
> struct device *dev = indio_dev->dev.parent;
>
> - adc->cfg->stop_conv(adc);
> + adc->cfg->stop_conv(indio_dev);
> if (!adc->dma_chan)
> stm32_adc_conv_irq_disable(adc);
>
> @@ -1891,7 +1901,7 @@ static int stm32_adc_probe(struct platform_device *pdev)
> indio_dev->info = &stm32_adc_iio_info;
> indio_dev->modes = INDIO_DIRECT_MODE | INDIO_HARDWARE_TRIGGERED;
>
> - platform_set_drvdata(pdev, adc);
> + platform_set_drvdata(pdev, indio_dev);
>
> ret = of_property_read_u32(pdev->dev.of_node, "reg", &adc->offset);
> if (ret != 0) {
> @@ -1905,7 +1915,7 @@ static int stm32_adc_probe(struct platform_device *pdev)
>
> ret = devm_request_threaded_irq(&pdev->dev, adc->irq, stm32_adc_isr,
> stm32_adc_threaded_isr,
> - 0, pdev->name, adc);
> + 0, pdev->name, indio_dev);
> if (ret) {
> dev_err(&pdev->dev, "failed to request IRQ\n");
> return ret;
> @@ -1989,8 +1999,8 @@ static int stm32_adc_probe(struct platform_device *pdev)
>
> static int stm32_adc_remove(struct platform_device *pdev)
> {
> - struct stm32_adc *adc = platform_get_drvdata(pdev);
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct iio_dev *indio_dev = platform_get_drvdata(pdev);
> + struct stm32_adc *adc = iio_priv(indio_dev);
>
> pm_runtime_get_sync(&pdev->dev);
> iio_device_unregister(indio_dev);
> @@ -2012,8 +2022,7 @@ static int stm32_adc_remove(struct platform_device *pdev)
> #if defined(CONFIG_PM_SLEEP)
> static int stm32_adc_suspend(struct device *dev)
> {
> - struct stm32_adc *adc = dev_get_drvdata(dev);
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
>
> if (iio_buffer_enabled(indio_dev))
> __stm32_adc_buffer_predisable(indio_dev);
> @@ -2023,8 +2032,7 @@ static int stm32_adc_suspend(struct device *dev)
>
> static int stm32_adc_resume(struct device *dev)
> {
> - struct stm32_adc *adc = dev_get_drvdata(dev);
> - struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> + struct iio_dev *indio_dev = dev_get_drvdata(dev);
> int ret;
>
> ret = pm_runtime_force_resume(dev);
>