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authorBen Dooks <ben@simtec.co.uk>2009-07-18 10:12:27 +0100
committerBen Dooks <ben-linux@fluff.org>2009-07-18 10:15:53 +0100
commite170adcb406504b8acd35554c69830c11916be1f (patch)
tree75a8aeb283e39d1b9b82bebfe347eb6c64def65f /arch/arm/plat-s3c24xx
parent885f9ebe7554628967b6e93b284dd3021e1bb280 (diff)
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 <ben@simtec.co.uk> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'arch/arm/plat-s3c24xx')
-rw-r--r--arch/arm/plat-s3c24xx/adc.c64
1 files changed, 53 insertions, 11 deletions
diff --git a/arch/arm/plat-s3c24xx/adc.c b/arch/arm/plat-s3c24xx/adc.c
index ee1baf11ad9e..11117a7ba911 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);