[media] vp702x: get rid of on-stack dma buffers

usb_control_msg initiates (and waits for completion of) a dma transfer using
the supplied buffer. That buffer thus has to be seperately allocated on
the heap.

In lib/dma_debug.c the function check_for_stack even warns about it:
	WARNING: at lib/dma-debug.c:866 check_for_stack

Note: This change is tested to compile only, as I don't have the hardware.

Signed-off-by: Florian Mickler <florian@mickler.org>
Cc: Patrick Boettcher <pb@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 63 insertions, 26 deletions

diff --git a/drivers/media/dvb/dvb-usb/vp702x-fe.c b/drivers/media/dvb/dvb-usb/vp702x-fe.c
index ccc7e4452664..7468a3839c5d 100644
--- a/drivers/media/dvb/dvb-usb/vp702x-fe.c
+++ b/drivers/media/dvb/dvb-usb/vp702x-fe.c
@@ -41,15 +41,26 @@ struct vp702x_fe_state {
 
 static int vp702x_fe_refresh_state(struct vp702x_fe_state *st)
 {
-        u8 buf[10];
-        if (time_after(jiffies,st->next_status_check)) {
-                vp702x_usb_in_op(st->d,READ_STATUS,0,0,buf,10);
-
+        u8 *buf;
+
+        if (time_after(jiffies, st->next_status_check)) {
+                buf = kmalloc(10, GFP_KERNEL);
+                if (!buf) {
+                        deb_fe("%s: buffer alloc failed\n", __func__);
+                        return -ENOMEM;
+                }
+                vp702x_usb_in_op(st->d, READ_STATUS, 0, 0, buf, 10);
                 st->lock = buf[4];
-                vp702x_usb_in_op(st->d,READ_TUNER_REG_REQ,0x11,0,&st->snr,1);
-                vp702x_usb_in_op(st->d,READ_TUNER_REG_REQ,0x15,0,&st->sig,1);
+
+                vp702x_usb_in_op(st->d, READ_TUNER_REG_REQ, 0x11, 0, buf, 1);
+                st->snr = buf[0];
+
+                vp702x_usb_in_op(st->d, READ_TUNER_REG_REQ, 0x15, 0, buf, 1);
+                st->sig = buf[0];
+
 
                 st->next_status_check = jiffies + (st->status_check_interval*HZ)/1000;
+                kfree(buf);
         }
         return 0;
 }
@@ -134,7 +145,11 @@ static int vp702x_fe_set_frontend(struct dvb_frontend* fe,
         /*CalFrequency*/
 /*      u16 frequencyRef[16] = { 2, 4, 8, 16, 32, 64, 128, 256, 24, 5, 10, 20, 40, 80, 160, 320 }; */
         u64 sr;
-        u8 cmd[8] = { 0 },ibuf[10];
+        u8 *cmd;
+
+        cmd = kzalloc(10, GFP_KERNEL);
+        if (!cmd)
+                return -ENOMEM;
 
         cmd[0] = (freq >> 8) & 0x7f;
         cmd[1] =  freq       & 0xff;
@@ -170,13 +185,14 @@ static int vp702x_fe_set_frontend(struct dvb_frontend* fe,
         st->status_check_interval = 250;
         st->next_status_check = jiffies;
 
-        vp702x_usb_inout_op(st->d,cmd,8,ibuf,10,100);
+        vp702x_usb_inout_op(st->d, cmd, 8, cmd, 10, 100);
 
-        if (ibuf[2] == 0 && ibuf[3] == 0)
+        if (cmd[2] == 0 && cmd[3] == 0)
                 deb_fe("tuning failed.\n");
         else
                 deb_fe("tuning succeeded.\n");
 
+        kfree(cmd);
         return 0;
 }
 
@@ -204,28 +220,36 @@ static int vp702x_fe_get_frontend(struct dvb_frontend* fe,
 static int vp702x_fe_send_diseqc_msg (struct dvb_frontend* fe,
                                     struct dvb_diseqc_master_cmd *m)
 {
+        int ret;
+        u8 *cmd;
         struct vp702x_fe_state *st = fe->demodulator_priv;
-        u8 cmd[8],ibuf[10];
-        memset(cmd,0,8);
+
+        cmd = kzalloc(10, GFP_KERNEL);
+        if (!cmd)
+                return -ENOMEM;
 
         deb_fe("%s\n",__func__);
 
-        if (m->msg_len > 4)
-                return -EINVAL;
+        if (m->msg_len > 4) {
+                ret = -EINVAL;
+                goto out;
+        }
 
         cmd[1] = SET_DISEQC_CMD;
         cmd[2] = m->msg_len;
         memcpy(&cmd[3], m->msg, m->msg_len);
-        cmd[7] = vp702x_chksum(cmd,0,7);
+        cmd[7] = vp702x_chksum(cmd, 0, 7);
 
-        vp702x_usb_inout_op(st->d,cmd,8,ibuf,10,100);
+        vp702x_usb_inout_op(st->d, cmd, 8, cmd, 10, 100);
 
-        if (ibuf[2] == 0 && ibuf[3] == 0)
+        if (cmd[2] == 0 && cmd[3] == 0)
                 deb_fe("diseqc cmd failed.\n");
         else
                 deb_fe("diseqc cmd succeeded.\n");
-
-        return 0;
+        ret = 0;
+out:
+        kfree(cmd);
+        return ret;
 }
 
 static int vp702x_fe_send_diseqc_burst (struct dvb_frontend* fe, fe_sec_mini_cmd_t burst)
@@ -237,9 +261,14 @@ static int vp702x_fe_send_diseqc_burst (struct dvb_frontend* fe, fe_sec_mini_cmd
 static int vp702x_fe_set_tone(struct dvb_frontend* fe, fe_sec_tone_mode_t tone)
 {
         struct vp702x_fe_state *st = fe->demodulator_priv;
-        u8 ibuf[10];
+        u8 *buf;
+
         deb_fe("%s\n",__func__);
 
+        buf = kmalloc(10, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+
         st->tone_mode = tone;
 
         if (tone == SEC_TONE_ON)
@@ -247,14 +276,16 @@ static int vp702x_fe_set_tone(struct dvb_frontend* fe, fe_sec_tone_mode_t tone)
         else
                 st->lnb_buf[2] = 0x00;
 
-        st->lnb_buf[7] = vp702x_chksum(st->lnb_buf,0,7);
+        st->lnb_buf[7] = vp702x_chksum(st->lnb_buf, 0, 7);
+        memcpy(buf, st->lnb_buf, 8);
 
-        vp702x_usb_inout_op(st->d,st->lnb_buf,8,ibuf,10,100);
-        if (ibuf[2] == 0 && ibuf[3] == 0)
+        vp702x_usb_inout_op(st->d, buf, 8, buf, 10, 100);
+        if (buf[2] == 0 && buf[3] == 0)
                 deb_fe("set_tone cmd failed.\n");
         else
                 deb_fe("set_tone cmd succeeded.\n");
 
+        kfree(buf);
         return 0;
 }
 
@@ -262,9 +293,13 @@ static int vp702x_fe_set_voltage (struct dvb_frontend* fe, fe_sec_voltage_t
                 voltage)
 {
         struct vp702x_fe_state *st = fe->demodulator_priv;
-        u8 ibuf[10];
+        u8 *buf;
         deb_fe("%s\n",__func__);
 
+        buf = kmalloc(10, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+
         st->voltage = voltage;
 
         if (voltage != SEC_VOLTAGE_OFF)
@@ -272,14 +307,16 @@ static int vp702x_fe_set_voltage (struct dvb_frontend* fe, fe_sec_voltage_t
         else
                 st->lnb_buf[4] = 0x00;
 
-        st->lnb_buf[7] = vp702x_chksum(st->lnb_buf,0,7);
+        st->lnb_buf[7] = vp702x_chksum(st->lnb_buf, 0, 7);
+        memcpy(buf, st->lnb_buf, 8);
 
-        vp702x_usb_inout_op(st->d,st->lnb_buf,8,ibuf,10,100);
-        if (ibuf[2] == 0 && ibuf[3] == 0)
+        vp702x_usb_inout_op(st->d, buf, 8, buf, 10, 100);
+        if (buf[2] == 0 && buf[3] == 0)
                 deb_fe("set_voltage cmd failed.\n");
         else
                 deb_fe("set_voltage cmd succeeded.\n");
 
+        kfree(buf);
         return 0;
 }