[ARM] S3C: ADC: Expose number of remaining conversions to

convert callback

This patch allow us to efficiently modify the number of
remaining conversions from the client side. This us useful
when we do not know in advance how many conversions we will
need or when we need to cancel pending conversions.

This change is simple enough to be compatible with existing
code that can just define the new pointer in the callback
and ignore it.

Sample usage:

http://tinyurl.com/s3c2410-ts-c (function stylus_adc_action).

Signed-off-by: Nelson Castillo <arhuaco@freaks-unidos.net>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

diff --git a/arch/arm/plat-s3c/include/plat/adc.h b/arch/arm/plat-s3c/include/plat/adc.h
index ef92e50ac0a72c35119525c7140fe6194151e801..d847bd476b6c29ffab98369250dc63b09a43025f 100644 (file)
--- a/arch/arm/plat-s3c/include/plat/adc.h
+++ b/arch/arm/plat-s3c/include/plat/adc.h
@@ -22,7 +22,8 @@ extern int s3c_adc_start(struct s3c_adc_client *client,
 extern struct s3c_adc_client *
        s3c_adc_register(struct platform_device *pdev,
                         void (*select)(unsigned selected),
-                        void (*conv)(unsigned d0, unsigned d1),
+                        void (*conv)(unsigned d0, unsigned d1,
+                                     unsigned *samples_left),
                         unsigned int is_ts);
 
 extern void s3c_adc_release(struct s3c_adc_client *client);

diff --git a/arch/arm/plat-s3c24xx/adc.c b/arch/arm/plat-s3c24xx/adc.c
index 91adfa71c1724f30b55a5d72c5e8bd25f32321bf..ee1baf11ad9e9851754a3514d1c6eb359f7de4ca 100644 (file)
--- a/arch/arm/plat-s3c24xx/adc.c
+++ b/arch/arm/plat-s3c24xx/adc.c
@@ -45,7 +45,8 @@ struct s3c_adc_client {
        unsigned char            channel;
 
        void    (*select_cb)(unsigned selected);
-       void    (*convert_cb)(unsigned val1, unsigned val2);
+       void    (*convert_cb)(unsigned val1, unsigned val2,
+                             unsigned *samples_left);
 };
 
 struct adc_device {
@@ -158,7 +159,8 @@ static void s3c_adc_default_select(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 (*conv)(unsigned d0, unsigned d1,
+                                                    unsigned *samples_left),
                                        unsigned int is_ts)
 {
        struct s3c_adc_client *client;
@@ -227,9 +229,10 @@ static irqreturn_t s3c_adc_irq(int irq, void *pw)
        data1 = readl(adc->regs + S3C2410_ADCDAT1);
        adc_dbg(adc, "read %d: 0x%04x, 0x%04x\n", client->nr_samples, data0, data1);
 
-       (client->convert_cb)(data0 & 0x3ff, data1 & 0x3ff);
+       client->nr_samples--;
+       (client->convert_cb)(data0 & 0x3ff, data1 & 0x3ff, &client->nr_samples);
 
-       if (--client->nr_samples > 0) {
+       if (client->nr_samples > 0) {
                /* fire another conversion for this */
 
                client->select_cb(1);