[media] cypress_firmware: refactor firmware downloading

Refactor firmware download function. It also should fix one bug
coming from usb_control_msg() message buffers. Taking buffers from
the stack for usb_control_msg() is not allowed as it does not work
on all architectures. Allocate buffers using kmalloc().

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 43 insertions, 37 deletions

diff --git a/drivers/media/usb/dvb-usb-v2/cypress_firmware.c b/drivers/media/usb/dvb-usb-v2/cypress_firmware.c
index bb21eeea5495..211df549f26a 100644
--- a/drivers/media/usb/dvb-usb-v2/cypress_firmware.c
+++ b/drivers/media/usb/dvb-usb-v2/cypress_firmware.c
@@ -40,48 +40,59 @@ static int usb_cypress_writemem(struct usb_device *udev, u16 addr, u8 *data,
 int usbv2_cypress_load_firmware(struct usb_device *udev,
                 const struct firmware *fw, int type)
 {
-        struct hexline hx;
-        u8 reset;
+        struct hexline *hx;
         int ret, pos = 0;
 
+        hx = kmalloc(sizeof(struct hexline), GFP_KERNEL);
+        if (!hx) {
+                dev_err(&udev->dev, "%s: kmalloc() failed\n", KBUILD_MODNAME);
+                return -ENOMEM;
+        }
+
         /* stop the CPU */
-        reset = 1;
-        ret = usb_cypress_writemem(udev, cypress[type].cs_reg, &reset, 1);
-        if (ret != 1)
-                dev_err(&udev->dev,
-                                "%s: could not stop the USB controller CPU\n",
-                                KBUILD_MODNAME);
-
-        while ((ret = dvb_usbv2_get_hexline(fw, &hx, &pos)) > 0) {
-                ret = usb_cypress_writemem(udev, hx.addr, hx.data, hx.len);
-                if (ret != hx.len) {
+        hx->data[0] = 1;
+        ret = usb_cypress_writemem(udev, cypress[type].cs_reg, hx->data, 1);
+        if (ret != 1) {
+                dev_err(&udev->dev, "%s: CPU stop failed=%d\n",
+                                KBUILD_MODNAME, ret);
+                ret = -EIO;
+                goto err_kfree;
+        }
+
+        /* write firmware to memory */
+        for (;;) {
+                ret = dvb_usbv2_get_hexline(fw, hx, &pos);
+                if (ret < 0)
+                        goto err_kfree;
+                else if (ret == 0)
+                        break;
+
+                ret = usb_cypress_writemem(udev, hx->addr, hx->data, hx->len);
+                if (ret < 0) {
+                        goto err_kfree;
+                } else if (ret != hx->len) {
                         dev_err(&udev->dev, "%s: error while transferring " \
                                         "firmware (transferred size=%d, " \
                                         "block size=%d)\n",
-                                        KBUILD_MODNAME, ret, hx.len);
-                        ret = -EINVAL;
-                        break;
+                                        KBUILD_MODNAME, ret, hx->len);
+                        ret = -EIO;
+                        goto err_kfree;
                 }
         }
-        if (ret < 0) {
-                dev_err(&udev->dev,
-                                "%s: firmware download failed at %d with %d\n",
-                                KBUILD_MODNAME, pos, ret);
-                return ret;
-        }
 
-        if (ret == 0) {
-                /* restart the CPU */
-                reset = 0;
-                if (ret || usb_cypress_writemem(
-                                udev, cypress[type].cs_reg, &reset, 1) != 1) {
-                        dev_err(&udev->dev, "%s: could not restart the USB " \
-                                        "controller CPU\n", KBUILD_MODNAME);
-                        ret = -EINVAL;
-                }
-        } else
+        /* start the CPU */
+        hx->data[0] = 0;
+        ret = usb_cypress_writemem(udev, cypress[type].cs_reg, hx->data, 1);
+        if (ret != 1) {
+                dev_err(&udev->dev, "%s: CPU start failed=%d\n",
+                                KBUILD_MODNAME, ret);
                 ret = -EIO;
+                goto err_kfree;
+        }
 
+        ret = 0;
+err_kfree:
+        kfree(hx);
         return ret;
 }
 EXPORT_SYMBOL(usbv2_cypress_load_firmware);
@@ -96,7 +107,6 @@ int dvb_usbv2_get_hexline(const struct firmware *fw, struct hexline *hx,
                 return 0;
 
         memset(hx, 0, sizeof(struct hexline));
-
         hx->len = b[0];
 
         if ((*pos + hx->len + 4) >= fw->size)
@@ -109,14 +119,10 @@ int dvb_usbv2_get_hexline(const struct firmware *fw, struct hexline *hx,
                 /* b[4] and b[5] are the Extended linear address record data
                  * field */
                 hx->addr |= (b[4] << 24) | (b[5] << 16);
-                /*
-                hx->len -= 2;
-                data_offs += 2;
-                */
         }
+
         memcpy(hx->data, &b[data_offs], hx->len);
         hx->chk = b[hx->len + data_offs];
-
         *pos += hx->len + 5;
 
         return *pos;