omapfb: dispc: allow multiple external IRQ handlers

Previously, the only external (to dispc.c) IRQ handler was RFBI's frame
done handler.  dispc's IRQ framework was very dumb: you could only have
one handler, and the semantics of {request,free}_irq were odd, to say the
least.

The new framework allows multiple consumers to register arbitrary IRQ
masks.

Signed-off-by: Daniel Stone <daniel.stone@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Imre Deak <imre.deak@nokia.com>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 67 insertions, 42 deletions

diff --git a/drivers/video/omap/dispc.c b/drivers/video/omap/dispc.c
index 04b7b8ae5583..80a11d078df4 100644
--- a/drivers/video/omap/dispc.c
+++ b/drivers/video/omap/dispc.c
@@ -155,6 +155,8 @@ struct resmap {
         unsigned long   *map;
 };
 
+#define MAX_IRQ_HANDLERS            4
+
 static struct {
         void __iomem    *base;
 
@@ -167,9 +169,11 @@ static struct {
 
         int             ext_mode;
 
-        unsigned long   enabled_irqs;
-        void            (*irq_callback)(void *);
-        void            *irq_callback_data;
+        struct {
+                u32     irq_mask;
+                void    (*callback)(void *);
+                void    *data;
+        } irq_handlers[MAX_IRQ_HANDLERS];
         struct completion       frame_done;
 
         int             fir_hinc[OMAPFB_PLANE_NUM];
@@ -809,56 +813,70 @@ static void set_lcd_timings(void)
         panel->pixel_clock = fck / lck_div / pck_div / 1000;
 }
 
-int omap_dispc_request_irq(void (*callback)(void *data), void *data)
+static void recalc_irq_mask(void)
 {
-        int r = 0;
+        int i;
+        unsigned long irq_mask = DISPC_IRQ_MASK_ERROR;
 
-        BUG_ON(callback == NULL);
+        for (i = 0; i < MAX_IRQ_HANDLERS; i++) {
+                if (!dispc.irq_handlers[i].callback)
+                        continue;
 
-        if (dispc.irq_callback)
-                r = -EBUSY;
-        else {
-                dispc.irq_callback = callback;
-                dispc.irq_callback_data = data;
+                irq_mask |= dispc.irq_handlers[i].irq_mask;
         }
 
-        return r;
-}
-EXPORT_SYMBOL(omap_dispc_request_irq);
-
-void omap_dispc_enable_irqs(int irq_mask)
-{
         enable_lcd_clocks(1);
-        dispc.enabled_irqs = irq_mask;
-        irq_mask |= DISPC_IRQ_MASK_ERROR;
         MOD_REG_FLD(DISPC_IRQENABLE, 0x7fff, irq_mask);
         enable_lcd_clocks(0);
 }
-EXPORT_SYMBOL(omap_dispc_enable_irqs);
 
-void omap_dispc_disable_irqs(int irq_mask)
+int omap_dispc_request_irq(unsigned long irq_mask, void (*callback)(void *data),
+                           void *data)
 {
-        enable_lcd_clocks(1);
-        dispc.enabled_irqs &= ~irq_mask;
-        irq_mask &= ~DISPC_IRQ_MASK_ERROR;
-        MOD_REG_FLD(DISPC_IRQENABLE, 0x7fff, irq_mask);
-        enable_lcd_clocks(0);
+        int i;
+
+        BUG_ON(callback == NULL);
+
+        for (i = 0; i < MAX_IRQ_HANDLERS; i++) {
+                if (dispc.irq_handlers[i].callback)
+                        continue;
+
+                dispc.irq_handlers[i].irq_mask = irq_mask;
+                dispc.irq_handlers[i].callback = callback;
+                dispc.irq_handlers[i].data = data;
+                recalc_irq_mask();
+
+                return 0;
+        }
+
+        return -EBUSY;
 }
-EXPORT_SYMBOL(omap_dispc_disable_irqs);
+EXPORT_SYMBOL(omap_dispc_request_irq);
 
-void omap_dispc_free_irq(void)
+void omap_dispc_free_irq(unsigned long irq_mask, void (*callback)(void *data),
+                         void *data)
 {
-        enable_lcd_clocks(1);
-        omap_dispc_disable_irqs(DISPC_IRQ_MASK_ALL);
-        dispc.irq_callback = NULL;
-        dispc.irq_callback_data = NULL;
-        enable_lcd_clocks(0);
+        int i;
+
+        for (i = 0; i < MAX_IRQ_HANDLERS; i++) {
+                if (dispc.irq_handlers[i].callback == callback &&
+                    dispc.irq_handlers[i].data == data) {
+                        dispc.irq_handlers[i].irq_mask = 0;
+                        dispc.irq_handlers[i].callback = NULL;
+                        dispc.irq_handlers[i].data = NULL;
+                        recalc_irq_mask();
+                        return;
+                }
+        }
+
+        BUG();
 }
 EXPORT_SYMBOL(omap_dispc_free_irq);
 
 static irqreturn_t omap_dispc_irq_handler(int irq, void *dev)
 {
         u32 stat;
+        int i = 0;
 
         enable_lcd_clocks(1);
 
@@ -873,8 +891,12 @@ static irqreturn_t omap_dispc_irq_handler(int irq, void *dev)
                 }
         }
 
-        if ((stat & dispc.enabled_irqs) && dispc.irq_callback)
-                dispc.irq_callback(dispc.irq_callback_data);
+        for (i = 0; i < MAX_IRQ_HANDLERS; i++) {
+                if (unlikely(dispc.irq_handlers[i].callback &&
+                             (stat & dispc.irq_handlers[i].irq_mask)))
+                        dispc.irq_handlers[i].callback(
+                                                dispc.irq_handlers[i].data);
+        }
 
         dispc_write_reg(DISPC_IRQSTATUS, stat);
 
@@ -1410,8 +1432,7 @@ static int omap_dispc_init(struct omapfb_device *fbdev, int ext_mode,
         l = dispc_read_reg(DISPC_IRQSTATUS);
         dispc_write_reg(DISPC_IRQSTATUS, l);
 
-        /* Enable those that we handle always */
-        omap_dispc_enable_irqs(DISPC_IRQ_FRAMEMASK);
+        recalc_irq_mask();
 
         if ((r = request_irq(INT_24XX_DSS_IRQ, omap_dispc_irq_handler,
                            0, MODULE_NAME, fbdev)) < 0) {
diff --git a/drivers/video/omap/dispc.h b/drivers/video/omap/dispc.h
index ef720a78f6d5..c15ea77f0604 100644
--- a/drivers/video/omap/dispc.h
+++ b/drivers/video/omap/dispc.h
@@ -37,9 +37,10 @@ extern void omap_dispc_set_lcd_size(int width, int height);
 extern void omap_dispc_enable_lcd_out(int enable);
 extern void omap_dispc_enable_digit_out(int enable);
 
-extern int  omap_dispc_request_irq(void (*callback)(void *data), void *data);
-extern void omap_dispc_free_irq(void);
+extern int omap_dispc_request_irq(unsigned long irq_mask,
+                                   void (*callback)(void *data), void *data);
+extern void omap_dispc_free_irq(unsigned long irq_mask,
+                                 void (*callback)(void *data), void *data);
 
 extern const struct lcd_ctrl omap2_int_ctrl;
-
 #endif
diff --git a/drivers/video/omap/rfbi.c b/drivers/video/omap/rfbi.c
index 9332d6ca6456..ee01e84e19c1 100644
--- a/drivers/video/omap/rfbi.c
+++ b/drivers/video/omap/rfbi.c
@@ -57,6 +57,7 @@
 
 #define DISPC_BASE              0x48050400
 #define DISPC_CONTROL           0x0040
+#define DISPC_IRQ_FRAMEMASK     0x0001
 
 static struct {
         void __iomem    *base;
@@ -553,7 +554,9 @@ static int rfbi_init(struct omapfb_device *fbdev)
         l = (0x01 << 2);
         rfbi_write_reg(RFBI_CONTROL, l);
 
-        if ((r = omap_dispc_request_irq(rfbi_dma_callback, NULL)) < 0) {
+        r = omap_dispc_request_irq(DISPC_IRQ_FRAMEMASK, rfbi_dma_callback,
+                                   NULL);
+        if (r < 0) {
                 dev_err(fbdev->dev, "can't get DISPC irq\n");
                 rfbi_enable_clocks(0);
                 return r;
@@ -570,7 +573,7 @@ static int rfbi_init(struct omapfb_device *fbdev)
 
 static void rfbi_cleanup(void)
 {
-        omap_dispc_free_irq();
+        omap_dispc_free_irq(DISPC_IRQ_FRAMEMASK, rfbi_dma_callback, NULL);
         rfbi_put_clocks();
         iounmap(rfbi.base);
 }