V4L/DVB: gspca_ov519: add support for the button on ov519 based cams

Note due to hardware limitiations (no interrupt endpoint), this only works
when the camera is streaming.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/drivers/media/video/gspca/ov519.c b/drivers/media/video/gspca/ov519.c
index 541b8f0b0d36..d9b89a2803df 100644
--- a/drivers/media/video/gspca/ov519.c
+++ b/drivers/media/video/gspca/ov519.c
@@ -38,6 +38,7 @@
  */
 #define MODULE_NAME "ov519"
 
+#include <linux/input.h>
 #include "gspca.h"
 
 MODULE_AUTHOR("Jean-Francois Moine <http://moinejf.free.fr>");
@@ -70,6 +71,9 @@ struct sd {
         char invert_led;
 #define BRIDGE_INVERT_LED       8
 
+        char snapshot_pressed;
+        char snapshot_needs_reset;
+
         /* Determined by sensor type */
         __u8 sif;
 
@@ -2685,6 +2689,26 @@ static void ov51x_led_control(struct sd *sd, int on)
         }
 }
 
+static void sd_reset_snapshot(struct gspca_dev *gspca_dev)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        if (!sd->snapshot_needs_reset)
+                return;
+
+        /* Note it is important that we clear sd->snapshot_needs_reset,
+           before actually clearing the snapshot state in the bridge
+           otherwise we might race with the pkt_scan interrupt handler */
+        sd->snapshot_needs_reset = 0;
+
+        switch (sd->bridge) {
+        case BRIDGE_OV519:
+                reg_w(sd, R51x_SYS_RESET, 0x40);
+                reg_w(sd, R51x_SYS_RESET, 0x00);
+                break;
+        }
+}
+
 static int ov51x_upload_quan_tables(struct sd *sd)
 {
         const unsigned char yQuanTable511[] = {
@@ -3921,6 +3945,12 @@ static int sd_start(struct gspca_dev *gspca_dev)
         setautobrightness(sd);
         setfreq(sd);
 
+        /* Force clear snapshot state in case the snapshot button was
+           pressed while we weren't streaming */
+        sd->snapshot_needs_reset = 1;
+        sd_reset_snapshot(gspca_dev);
+        sd->snapshot_pressed = 0;
+
         ret = ov51x_restart(sd);
         if (ret < 0)
                 goto out;
@@ -4033,6 +4063,30 @@ static void ov518_pkt_scan(struct gspca_dev *gspca_dev,
         gspca_frame_add(gspca_dev, INTER_PACKET, data, len);
 }
 
+static void ov519_handle_button(struct gspca_dev *gspca_dev, u8 state)
+{
+        struct sd *sd = (struct sd *) gspca_dev;
+
+        /* This should never happen, but better to check */
+        if (state != 0 && state != 1)
+                return;
+
+        /* We may need to reset the button state multiple times, as resetting
+           does not work as long as the button stays pressed, so always set
+           snapshot_needs_reset (instead of only on a state change to 1). */
+        if (state)
+                sd->snapshot_needs_reset = 1;
+
+        if (sd->snapshot_pressed != state) {
+#ifdef CONFIG_INPUT
+                input_report_key(gspca_dev->input_dev, KEY_CAMERA, state);
+                input_sync(gspca_dev->input_dev);
+#endif
+
+                sd->snapshot_pressed = state;
+        }
+}
+
 static void ov519_pkt_scan(struct gspca_dev *gspca_dev,
                         u8 *data,                       /* isoc packet */
                         int len)                        /* iso packet length */
@@ -4052,6 +4106,9 @@ static void ov519_pkt_scan(struct gspca_dev *gspca_dev,
         if (data[0] == 0xff && data[1] == 0xff && data[2] == 0xff) {
                 switch (data[3]) {
                 case 0x50:              /* start of frame */
+                        /* Don't check the button state here, as the state
+                           usually (always ?) changes at EOF and checking it
+                           here leads to unnecessary snapshot state resets. */
 #define HDRSZ 16
                         data += HDRSZ;
                         len -= HDRSZ;
@@ -4063,6 +4120,7 @@ static void ov519_pkt_scan(struct gspca_dev *gspca_dev,
                                 gspca_dev->last_packet_type = DISCARD_PACKET;
                         return;
                 case 0x51:              /* end of frame */
+                        ov519_handle_button(gspca_dev, data[11]);
                         if (data[9] != 0)
                                 gspca_dev->last_packet_type = DISCARD_PACKET;
                         gspca_frame_add(gspca_dev, LAST_PACKET,
@@ -4505,9 +4563,13 @@ static const struct sd_desc sd_desc = {
         .stopN = sd_stopN,
         .stop0 = sd_stop0,
         .pkt_scan = sd_pkt_scan,
+        .dq_callback = sd_reset_snapshot,
         .querymenu = sd_querymenu,
         .get_jcomp = sd_get_jcomp,
         .set_jcomp = sd_set_jcomp,
+#ifdef CONFIG_INPUT
+        .other_input = 1,
+#endif
 };
 
 /* -- module initialisation -- */