[PATCHv6 1/4] iio: adc: exynos_adc: Add exynos_adc_data structure to improve readability

Chanwoo Choi
2014-07-18T05:59:43Z

This patchset add 'exynos_adc_data' structure which includes some functions
to control ADC operation and specific data according to ADC version (v1 or v2).

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
---
drivers/iio/adc/exynos_adc.c | 226 ++++++++++++++++++++++++++++---------------
1 file changed, 147 insertions(+), 79 deletions(-)

diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
index 010578f..00d67fd 100644
--- a/drivers/iio/adc/exynos_adc.c
+++ b/drivers/iio/adc/exynos_adc.c
@@ -39,11 +39,6 @@
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>

-enum adc_version {
- ADC_V1,
- ADC_V2
-};
-
/* EXYNOS4412/5250 ADC_V1 registers definitions */
#define ADC_V1_CON(x) ((x) + 0x00)
#define ADC_V1_DLY(x) ((x) + 0x08)
@@ -85,6 +80,7 @@ enum adc_version {
#define EXYNOS_ADC_TIMEOUT (msecs_to_jiffies(100))

struct exynos_adc {
+ struct exynos_adc_data *data;
void __iomem *regs;
void __iomem *enable_reg;
struct clk *clk;
@@ -97,43 +93,139 @@ struct exynos_adc {
unsigned int version;
};

-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 },
- {},
+struct exynos_adc_data {
+ int num_channels;
+
+ void (*init_hw)(struct exynos_adc *info);
+ void (*exit_hw)(struct exynos_adc *info);
+ void (*clear_irq)(struct exynos_adc *info);
+ void (*start_conv)(struct exynos_adc *info, unsigned long addr);
};
-MODULE_DEVICE_TABLE(of, exynos_adc_match);

-static inline unsigned int exynos_adc_get_version(struct platform_device *pdev)
+static void exynos_adc_v1_init_hw(struct exynos_adc *info)
{
- const struct of_device_id *match;
+ u32 con1;

- match = of_match_node(exynos_adc_match, pdev->dev.of_node);
- return (unsigned int)match->data;
+ writel(1, info->enable_reg);
+
+ /* 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_exit_hw(struct exynos_adc *info)
+{
+ u32 con;
+
+ writel(0, info->enable_reg);
+
+ con = readl(ADC_V1_CON(info->regs));
+ con |= ADC_V1_CON_STANDBY;
+ writel(con, 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_hw_init(struct exynos_adc *info)
+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 struct exynos_adc_data const exynos_adc_v1_data = {
+ .num_channels = MAX_ADC_V1_CHANNELS,
+
+ .init_hw = exynos_adc_v1_init_hw,
+ .exit_hw = exynos_adc_v1_exit_hw,
+ .clear_irq = exynos_adc_v1_clear_irq,
+ .start_conv = exynos_adc_v1_start_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));
+ writel(1, info->enable_reg);

- 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));
+ con1 = ADC_V2_CON1_SOFT_RESET;
+ writel(con1, ADC_V2_CON1(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;
+ 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 12-bit ADC resolution */
- con1 |= ADC_V1_CON_RES;
- writel(con1, ADC_V1_CON(info->regs));
- }
+ /* Enable interrupts */
+ writel(1, ADC_V2_INT_EN(info->regs));
+}
+
+static void exynos_adc_v2_exit_hw(struct exynos_adc *info)
+{
+ u32 con;
+
+ writel(0, info->enable_reg);
+
+ con = readl(ADC_V2_CON1(info->regs));
+ con &= ~ADC_CON_EN_START;
+ writel(con, 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_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 struct exynos_adc_data const exynos_adc_v2_data = {
+ .num_channels = MAX_ADC_V2_CHANNELS,
+
+ .init_hw = exynos_adc_v2_init_hw,
+ .exit_hw = exynos_adc_v2_exit_hw,
+ .clear_irq = exynos_adc_v2_clear_irq,
+ .start_conv = exynos_adc_v2_start_conv,
+};
+
+static const struct of_device_id exynos_adc_match[] = {
+ {
+ .compatible = "samsung,exynos-adc-v1",
+ .data = (void *)&exynos_adc_v1_data,
+ }, {
+ .compatible = "samsung,exynos-adc-v2",
+ .data = (void *)&exynos_adc_v2_data,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, exynos_adc_match);
+
+static struct exynos_adc_data *exynos_adc_get_data(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
+
+ match = of_match_node(exynos_adc_match, pdev->dev.of_node);
+ return (struct exynos_adc_data *)match->data;
}

static int exynos_read_raw(struct iio_dev *indio_dev,
@@ -144,7 +236,6 @@ 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 +245,15 @@ 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->data->start_conv)
+ info->data->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->data->init_hw)
+ info->data->init_hw(info);
ret = -ETIMEDOUT;
} else {
*val = info->value;
@@ -193,13 +271,11 @@ 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->data->clear_irq)
+ info->data->clear_irq(info);

complete(&info->completion);

@@ -277,6 +353,12 @@ static int exynos_adc_probe(struct platform_device *pdev)

info = iio_priv(indio_dev);

+ info->data = exynos_adc_get_data(pdev);
+ if (!info->data) {
+ dev_err(&pdev->dev, "failed getting exynos_adc_data\n");
+ return -EINVAL;
+ }
+
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
info->regs = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(info->regs))
@@ -319,10 +401,6 @@ static int exynos_adc_probe(struct platform_device *pdev)
if (ret)
goto err_disable_reg;

- 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);
@@ -331,11 +409,7 @@ static int exynos_adc_probe(struct platform_device *pdev)
indio_dev->info = &exynos_adc_iio_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = exynos_adc_iio_channels;
-
- if (info->version == ADC_V1)
- indio_dev->num_channels = MAX_ADC_V1_CHANNELS;
- else
- indio_dev->num_channels = MAX_ADC_V2_CHANNELS;
+ indio_dev->num_channels = info->data->num_channels;

ret = request_irq(info->irq, exynos_adc_isr,
0, dev_name(&pdev->dev), info);
@@ -349,7 +423,8 @@ static int exynos_adc_probe(struct platform_device *pdev)
if (ret)
goto err_irq;

- exynos_adc_hw_init(info);
+ if (info->data->init_hw)
+ info->data->init_hw(info);

ret = of_platform_populate(np, exynos_adc_match, NULL, &indio_dev->dev);
if (ret < 0) {
@@ -366,7 +441,8 @@ err_of_populate:
err_irq:
free_irq(info->irq, info);
err_disable_clk:
- writel(0, info->enable_reg);
+ if (info->data->exit_hw)
+ info->data->exit_hw(info);
clk_disable_unprepare(info->clk);
err_disable_reg:
regulator_disable(info->vdd);
@@ -382,7 +458,8 @@ static int exynos_adc_remove(struct platform_device *pdev)
exynos_adc_remove_devices);
iio_device_unregister(indio_dev);
free_irq(info->irq, info);
- writel(0, info->enable_reg);
+ if (info->data->exit_hw)
+ info->data->exit_hw(info);
clk_disable_unprepare(info->clk);
regulator_disable(info->vdd);

@@ -394,19 +471,10 @@ 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->data->exit_hw)
+ info->data->exit_hw(info);

- writel(0, info->enable_reg);
clk_disable_unprepare(info->clk);
regulator_disable(info->vdd);

@@ -427,8 +495,8 @@ static int exynos_adc_resume(struct device *dev)
if (ret)
return ret;

- writel(1, info->enable_reg);
- exynos_adc_hw_init(info);
+ if (info->data->init_hw)
+ info->data->init_hw(info);

return 0;
}
--
1.8.0