diff options
Diffstat (limited to 'arch/arm/plat-s3c24xx/adc.c')
-rw-r--r-- | arch/arm/plat-s3c24xx/adc.c | 119 |
1 files changed, 103 insertions, 16 deletions
diff --git a/arch/arm/plat-s3c24xx/adc.c b/arch/arm/plat-s3c24xx/adc.c index ee1baf11ad9..8c443153d05 100644 --- a/arch/arm/plat-s3c24xx/adc.c +++ b/arch/arm/plat-s3c24xx/adc.c @@ -14,6 +14,7 @@ #include <linux/module.h> #include <linux/kernel.h> #include <linux/platform_device.h> +#include <linux/sched.h> #include <linux/list.h> #include <linux/err.h> #include <linux/clk.h> @@ -39,13 +40,17 @@ struct s3c_adc_client { struct platform_device *pdev; struct list_head pend; + wait_queue_head_t *wait; unsigned int nr_samples; + int result; unsigned char is_ts; unsigned char channel; + unsigned int selected; - void (*select_cb)(unsigned selected); - void (*convert_cb)(unsigned val1, unsigned val2, + void (*select_cb)(struct s3c_adc_client *c, unsigned selected); + void (*convert_cb)(struct s3c_adc_client *c, + unsigned val1, unsigned val2, unsigned *samples_left); }; @@ -58,20 +63,31 @@ struct adc_device { void __iomem *regs; unsigned int prescale; + unsigned int delay; int irq; }; static struct adc_device *adc_dev; +static struct work_struct resume_work; + static LIST_HEAD(adc_pending); #define adc_dbg(_adc, msg...) dev_dbg(&(_adc)->pdev->dev, msg) +#define AUTOPST (S3C2410_ADCTSC_YM_SEN | S3C2410_ADCTSC_YP_SEN | \ + S3C2410_ADCTSC_XP_SEN | S3C2410_ADCTSC_AUTO_PST | \ + S3C2410_ADCTSC_XY_PST(0)) + static inline void s3c_adc_convert(struct adc_device *adc) { unsigned con = readl(adc->regs + S3C2410_ADCCON); + if (adc->cur->is_ts) + writel(S3C2410_ADCTSC_PULL_UP_DISABLE | AUTOPST, + adc->regs + S3C2410_ADCTSC); + con |= S3C2410_ADCCON_ENABLE_START; writel(con, adc->regs + S3C2410_ADCCON); } @@ -81,7 +97,10 @@ static inline void s3c_adc_select(struct adc_device *adc, { unsigned con = readl(adc->regs + S3C2410_ADCCON); - client->select_cb(1); + if (!client->selected) { + client->selected = 1; + client->select_cb(client, 1); + } con &= ~S3C2410_ADCCON_MUXMASK; con &= ~S3C2410_ADCCON_STDBM; @@ -105,12 +124,9 @@ static void s3c_adc_try(struct adc_device *adc) { struct s3c_adc_client *next = adc->ts_pend; - if (!next && !list_empty(&adc_pending)) { + if (!next && !list_empty(&adc_pending)) next = list_first_entry(&adc_pending, struct s3c_adc_client, pend); - list_del(&next->pend); - } else - adc->ts_pend = NULL; if (next) { adc_dbg(adc, "new client is %p\n", next); @@ -153,25 +169,61 @@ int s3c_adc_start(struct s3c_adc_client *client, } EXPORT_SYMBOL_GPL(s3c_adc_start); -static void s3c_adc_default_select(unsigned select) +static void s3c_convert_done(struct s3c_adc_client *client, + unsigned v, unsigned u, unsigned *left) +{ + client->result = v; + wake_up(client->wait); +} + +int s3c_adc_read(struct s3c_adc_client *client, unsigned int ch) +{ + DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake); + int ret; + + client->convert_cb = s3c_convert_done; + client->wait = &wake; + client->result = -1; + + ret = s3c_adc_start(client, ch, 1); + if (ret < 0) + goto err; + + ret = wait_event_timeout(wake, client->result >= 0, HZ / 2); + if (client->result < 0) { + ret = -ETIMEDOUT; + goto err; + } + + client->convert_cb = NULL; + return client->result; + +err: + return ret; +} +EXPORT_SYMBOL_GPL(s3c_adc_read); + +static void s3c_adc_default_select(struct s3c_adc_client *client, + unsigned select) { } struct s3c_adc_client *s3c_adc_register(struct platform_device *pdev, - void (*select)(unsigned int selected), - void (*conv)(unsigned d0, unsigned d1, + void (*select)(struct s3c_adc_client *client, + unsigned int selected), + void (*conv)(struct s3c_adc_client *client, + unsigned d0, unsigned d1, unsigned *samples_left), unsigned int is_ts) { struct s3c_adc_client *client; WARN_ON(!pdev); - WARN_ON(!conv); if (!select) select = s3c_adc_default_select; - if (!conv || !pdev) + if (!pdev) return ERR_PTR(-EINVAL); client = kzalloc(sizeof(struct s3c_adc_client), GFP_KERNEL); @@ -230,18 +282,27 @@ static irqreturn_t s3c_adc_irq(int irq, void *pw) adc_dbg(adc, "read %d: 0x%04x, 0x%04x\n", client->nr_samples, data0, data1); client->nr_samples--; - (client->convert_cb)(data0 & 0x3ff, data1 & 0x3ff, &client->nr_samples); + + if (client->convert_cb) + (client->convert_cb)(client, data0 & 0x3ff, data1 & 0x3ff, + &client->nr_samples); if (client->nr_samples > 0) { /* fire another conversion for this */ - - client->select_cb(1); + client->selected = 1; + client->select_cb(client, 1); s3c_adc_convert(adc); } else { local_irq_save(flags); - (client->select_cb)(0); + client->selected = 0; + if (!adc->cur->is_ts) + list_del(&adc->cur->pend); + else + adc->ts_pend = NULL; adc->cur = NULL; + (client->select_cb)(client, 0); + s3c_adc_try(adc); local_irq_restore(flags); } @@ -264,6 +325,7 @@ static int s3c_adc_probe(struct platform_device *pdev) adc->pdev = pdev; adc->prescale = S3C2410_ADCCON_PRSCVL(49); + adc->delay = 0x2710; adc->irq = platform_get_irq(pdev, 1); if (adc->irq <= 0) { @@ -303,6 +365,7 @@ static int s3c_adc_probe(struct platform_device *pdev) writel(adc->prescale | S3C2410_ADCCON_PRSCEN, adc->regs + S3C2410_ADCCON); + writel(adc->delay, adc->regs + S3C2410_ADCDLY); dev_info(dev, "attached adc driver\n"); @@ -346,18 +409,42 @@ static int s3c_adc_suspend(struct platform_device *pdev, pm_message_t state) writel(con, adc->regs + S3C2410_ADCCON); clk_disable(adc->clk); + disable_irq(IRQ_ADC); + if (!list_empty(&adc_pending) || adc->ts_pend) + dev_info(&pdev->dev, "We still have adc clients pending\n"); return 0; } +/* It seems this is not needed. This is under upstream review now. */ +static void adc_resume_work(struct work_struct *work) +{ + if (!adc_dev) /* Have no ADC here */ + return; + + if (!list_empty(&adc_pending) || adc_dev->ts_pend) + /* We still have adc clients pending */ + s3c_adc_try(adc_dev); +} + static int s3c_adc_resume(struct platform_device *pdev) { struct adc_device *adc = platform_get_drvdata(pdev); + enable_irq(IRQ_ADC); clk_enable(adc->clk); writel(adc->prescale | S3C2410_ADCCON_PRSCEN, adc->regs + S3C2410_ADCCON); + writel(adc->delay, adc->regs + S3C2410_ADCDLY); + + /* Schedule task if there are clients pending. */ + if (!list_empty(&adc_pending) || adc_dev->ts_pend) { + INIT_WORK(&resume_work, adc_resume_work); + if (!schedule_work(&resume_work)) + dev_err(&pdev->dev, + "Failed to schedule adc_resume work!\n"); + } return 0; } |