From e170adcb406504b8acd35554c69830c11916be1f Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Sat, 18 Jul 2009 10:12:27 +0100 Subject: ARM: S3C: Add ADC synchronous read call. To add HWMON support, we need a synchronous read() call that blocks until completion. Add the client that is being service to the select and convert callbacks to make the code easier. Signed-off-by: Ben Dooks Signed-off-by: Ben Dooks --- arch/arm/plat-s3c24xx/adc.c | 64 +++++++++++++++++++++++++++++++++++++-------- 1 file changed, 53 insertions(+), 11 deletions(-) (limited to 'arch/arm/plat-s3c24xx/adc.c') diff --git a/arch/arm/plat-s3c24xx/adc.c b/arch/arm/plat-s3c24xx/adc.c index ee1baf11ad9..11117a7ba91 100644 --- a/arch/arm/plat-s3c24xx/adc.c +++ b/arch/arm/plat-s3c24xx/adc.c @@ -39,13 +39,16 @@ 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; - 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); }; @@ -81,7 +84,7 @@ static inline void s3c_adc_select(struct adc_device *adc, { unsigned con = readl(adc->regs + S3C2410_ADCCON); - client->select_cb(1); + client->select_cb(client, 1); con &= ~S3C2410_ADCCON_MUXMASK; con &= ~S3C2410_ADCCON_STDBM; @@ -153,25 +156,61 @@ 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_convert); + +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); @@ -230,16 +269,19 @@ 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->select_cb(client, 1); s3c_adc_convert(adc); } else { local_irq_save(flags); - (client->select_cb)(0); + (client->select_cb)(client, 0); adc->cur = NULL; s3c_adc_try(adc); -- cgit v1.2.3