Re: [PATCHv4 1/4] iio: adc: exynos_adc: Add exynos_adc_ops structure to improve readability

From: Naveen Krishna Ch
Date: Wed Jun 18 2014 - 01:28:04 EST


Hello Chanwoo,

On 18 June 2014 07:50, Chanwoo Choi <cw00.choi@xxxxxxxxxxx> wrote:
> This patchset add 'exynos_adc_ops' structure which includes some functions
> to control ADC operation according to ADC version (v1 or v2).
>
> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> Acked-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>

This is a good piece of change, Thanks.

Reviewed-by: Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx>
> ---
> drivers/iio/adc/exynos_adc.c | 174 +++++++++++++++++++++++++++++--------------
> 1 file changed, 120 insertions(+), 54 deletions(-)
>
> diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
> index 010578f..c30def6 100644
> --- a/drivers/iio/adc/exynos_adc.c
> +++ b/drivers/iio/adc/exynos_adc.c
> @@ -90,6 +90,7 @@ struct exynos_adc {
> struct clk *clk;
> unsigned int irq;
> struct regulator *vdd;
> + struct exynos_adc_ops *ops;
>
> struct completion completion;
>
> @@ -97,6 +98,13 @@ struct exynos_adc {
> unsigned int version;
> };
>
> +struct exynos_adc_ops {
> + void (*init_hw)(struct exynos_adc *info);
> + void (*clear_irq)(struct exynos_adc *info);
> + void (*start_conv)(struct exynos_adc *info, unsigned long addr);
> + void (*stop_conv)(struct exynos_adc *info);
> +};
> +
> static const struct of_device_id exynos_adc_match[] = {
> { .compatible = "samsung,exynos-adc-v1", .data = (void *)ADC_V1 },
> { .compatible = "samsung,exynos-adc-v2", .data = (void *)ADC_V2 },
> @@ -112,30 +120,98 @@ static inline unsigned int exynos_adc_get_version(struct platform_device *pdev)
> return (unsigned int)match->data;
> }
>
> -static void exynos_adc_hw_init(struct exynos_adc *info)
> +static void exynos_adc_v1_init_hw(struct exynos_adc *info)
> +{
> + u32 con1;
> +
> + /* set default prescaler values and Enable prescaler */
> + con1 = ADC_V1_CON_PRSCLV(49) | ADC_V1_CON_PRSCEN;
> +
> + /* Enable 12-bit ADC resolution */
> + con1 |= ADC_V1_CON_RES;
> + writel(con1, ADC_V1_CON(info->regs));
> +}
> +
> +static void exynos_adc_v1_start_conv(struct exynos_adc *info, unsigned long addr)
> +{
> + u32 con1;
> +
> + writel(addr, ADC_V1_MUX(info->regs));
> +
> + con1 = readl(ADC_V1_CON(info->regs));
> + writel(con1 | ADC_CON_EN_START, ADC_V1_CON(info->regs));
> +}
> +
> +static void exynos_adc_v1_clear_irq(struct exynos_adc *info)
> +{
> + writel(1, ADC_V1_INTCLR(info->regs));
> +}
> +
> +static void exynos_adc_v1_stop_conv(struct exynos_adc *info)
> +{
> + u32 con;
> +
> + con = readl(ADC_V1_CON(info->regs));
> + con |= ADC_V1_CON_STANDBY;
> + writel(con, ADC_V1_CON(info->regs));
> +}
> +
> +static struct exynos_adc_ops exynos_adc_v1_ops = {
> + .init_hw = exynos_adc_v1_init_hw,
> + .clear_irq = exynos_adc_v1_clear_irq,
> + .start_conv = exynos_adc_v1_start_conv,
> + .stop_conv = exynos_adc_v1_stop_conv,
> +};
> +
> +static void exynos_adc_v2_init_hw(struct exynos_adc *info)
> {
> u32 con1, con2;
>
> - if (info->version == ADC_V2) {
> - con1 = ADC_V2_CON1_SOFT_RESET;
> - writel(con1, ADC_V2_CON1(info->regs));
> + con1 = ADC_V2_CON1_SOFT_RESET;
> + writel(con1, ADC_V2_CON1(info->regs));
>
> - con2 = ADC_V2_CON2_OSEL | ADC_V2_CON2_ESEL |
> - ADC_V2_CON2_HIGHF | ADC_V2_CON2_C_TIME(0);
> - writel(con2, ADC_V2_CON2(info->regs));
> + con2 = ADC_V2_CON2_OSEL | ADC_V2_CON2_ESEL |
> + ADC_V2_CON2_HIGHF | ADC_V2_CON2_C_TIME(0);
> + writel(con2, ADC_V2_CON2(info->regs));
>
> - /* Enable interrupts */
> - writel(1, ADC_V2_INT_EN(info->regs));
> - } else {
> - /* set default prescaler values and Enable prescaler */
> - con1 = ADC_V1_CON_PRSCLV(49) | ADC_V1_CON_PRSCEN;
> + /* Enable interrupts */
> + writel(1, ADC_V2_INT_EN(info->regs));
> +}
>
> - /* Enable 12-bit ADC resolution */
> - con1 |= ADC_V1_CON_RES;
> - writel(con1, ADC_V1_CON(info->regs));
> - }
> +static void exynos_adc_v2_start_conv(struct exynos_adc *info, unsigned long addr)
> +{
> + u32 con1, con2;
> +
> + con2 = readl(ADC_V2_CON2(info->regs));
> + con2 &= ~ADC_V2_CON2_ACH_MASK;
> + con2 |= ADC_V2_CON2_ACH_SEL(addr);
> + writel(con2, ADC_V2_CON2(info->regs));
> +
> + con1 = readl(ADC_V2_CON1(info->regs));
> + writel(con1 | ADC_CON_EN_START, ADC_V2_CON1(info->regs));
> +}
> +
> +static void exynos_adc_v2_clear_irq(struct exynos_adc *info)
> +{
> + writel(1, ADC_V2_INT_ST(info->regs));
> +}
> +
> +static void exynos_adc_v2_stop_conv(struct exynos_adc *info)
> +{
> + u32 con;
> +
> + con = readl(ADC_V2_CON1(info->regs));
> + con &= ~ADC_CON_EN_START;
> + writel(con, ADC_V2_CON1(info->regs));
> }
>
> +static struct exynos_adc_ops exynos_adc_v2_ops = {
> + .init_hw = exynos_adc_v2_init_hw,
> + .start_conv = exynos_adc_v2_start_conv,
> + .clear_irq = exynos_adc_v2_clear_irq,
> + .stop_conv = exynos_adc_v2_stop_conv,
> +};
> +
> static int exynos_read_raw(struct iio_dev *indio_dev,
> struct iio_chan_spec const *chan,
> int *val,
> @@ -144,7 +220,6 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
> {
> struct exynos_adc *info = iio_priv(indio_dev);
> unsigned long timeout;
> - u32 con1, con2;
> int ret;
>
> if (mask != IIO_CHAN_INFO_RAW)
> @@ -154,28 +229,15 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
> reinit_completion(&info->completion);
>
> /* Select the channel to be used and Trigger conversion */
> - if (info->version == ADC_V2) {
> - con2 = readl(ADC_V2_CON2(info->regs));
> - con2 &= ~ADC_V2_CON2_ACH_MASK;
> - con2 |= ADC_V2_CON2_ACH_SEL(chan->address);
> - writel(con2, ADC_V2_CON2(info->regs));
> -
> - con1 = readl(ADC_V2_CON1(info->regs));
> - writel(con1 | ADC_CON_EN_START,
> - ADC_V2_CON1(info->regs));
> - } else {
> - writel(chan->address, ADC_V1_MUX(info->regs));
> -
> - con1 = readl(ADC_V1_CON(info->regs));
> - writel(con1 | ADC_CON_EN_START,
> - ADC_V1_CON(info->regs));
> - }
> + if (info->ops->start_conv)
> + info->ops->start_conv(info, chan->address);
>
> timeout = wait_for_completion_timeout
> (&info->completion, EXYNOS_ADC_TIMEOUT);
> if (timeout == 0) {
> dev_warn(&indio_dev->dev, "Conversion timed out! Resetting\n");
> - exynos_adc_hw_init(info);
> + if (info->ops->init_hw)
> + info->ops->init_hw(info);
> ret = -ETIMEDOUT;
> } else {
> *val = info->value;
> @@ -193,13 +255,11 @@ static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
> struct exynos_adc *info = (struct exynos_adc *)dev_id;
>
> /* Read value */
> - info->value = readl(ADC_V1_DATX(info->regs)) &
> - ADC_DATX_MASK;
> + info->value = readl(ADC_V1_DATX(info->regs)) & ADC_DATX_MASK;
> +
> /* clear irq */
> - if (info->version == ADC_V2)
> - writel(1, ADC_V2_INT_ST(info->regs));
> - else
> - writel(1, ADC_V1_INTCLR(info->regs));
> + if (info->ops->clear_irq)
> + info->ops->clear_irq(info);
>
> complete(&info->completion);
>
> @@ -277,6 +337,19 @@ static int exynos_adc_probe(struct platform_device *pdev)
>
> info = iio_priv(indio_dev);
>
> + info->version = exynos_adc_get_version(pdev);
> + switch (info->version) {
> + case ADC_V1:
> + info->ops = &exynos_adc_v1_ops;
> + break;
> + case ADC_V2:
> + info->ops = &exynos_adc_v2_ops;
> + break;
> + default:
> + dev_err(&pdev->dev, "failed to identify ADC version\n");
> + return -EINVAL;
> + };
> +
> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> info->regs = devm_ioremap_resource(&pdev->dev, mem);
> if (IS_ERR(info->regs))
> @@ -321,8 +394,6 @@ static int exynos_adc_probe(struct platform_device *pdev)
>
> writel(1, info->enable_reg);
>
> - info->version = exynos_adc_get_version(pdev);
> -
> platform_set_drvdata(pdev, indio_dev);
>
> indio_dev->name = dev_name(&pdev->dev);
> @@ -349,7 +420,8 @@ static int exynos_adc_probe(struct platform_device *pdev)
> if (ret)
> goto err_irq;
>
> - exynos_adc_hw_init(info);
> + if (info->ops->init_hw)
> + info->ops->init_hw(info);
>
> ret = of_platform_populate(np, exynos_adc_match, NULL, &indio_dev->dev);
> if (ret < 0) {
> @@ -394,17 +466,9 @@ static int exynos_adc_suspend(struct device *dev)
> {
> struct iio_dev *indio_dev = dev_get_drvdata(dev);
> struct exynos_adc *info = iio_priv(indio_dev);
> - u32 con;
>
> - if (info->version == ADC_V2) {
> - con = readl(ADC_V2_CON1(info->regs));
> - con &= ~ADC_CON_EN_START;
> - writel(con, ADC_V2_CON1(info->regs));
> - } else {
> - con = readl(ADC_V1_CON(info->regs));
> - con |= ADC_V1_CON_STANDBY;
> - writel(con, ADC_V1_CON(info->regs));
> - }
> + if (info->ops->stop_conv)
> + info->ops->stop_conv(info);
>
> writel(0, info->enable_reg);
> clk_disable_unprepare(info->clk);
> @@ -428,7 +492,9 @@ static int exynos_adc_resume(struct device *dev)
> return ret;
>
> writel(1, info->enable_reg);
> - exynos_adc_hw_init(info);
> +
> + if (info->ops->init_hw)
> + info->ops->init_hw(info);
>
> return 0;
> }
> --
> 1.8.0
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html



--
Shine bright,
(: Nav :)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/