Re: [PATCH 07/26] dib0700: be sure that dib0700_ctrl_rd() users can do DMA

From: Patrick Boettcher
Date: Mon Oct 10 2016 - 02:38:44 EST


On Fri, 7 Oct 2016 14:24:17 -0300
Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> wrote:

> dib0700_ctrl_rd() takes a RX and a TX pointer. Be sure that
> both will point to a memory allocated via kmalloc().
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/usb/dvb-usb/dib0700_core.c | 4 +++-
> drivers/media/usb/dvb-usb/dib0700_devices.c | 25
> +++++++++++++------------ 2 files changed, 16 insertions(+), 13
> deletions(-)
>
> diff --git a/drivers/media/usb/dvb-usb/dib0700_core.c
> b/drivers/media/usb/dvb-usb/dib0700_core.c index
> f3196658fb70..515f89dba199 100644 ---
> a/drivers/media/usb/dvb-usb/dib0700_core.c +++
> b/drivers/media/usb/dvb-usb/dib0700_core.c @@ -292,13 +292,15 @@
> static int dib0700_i2c_xfer_legacy(struct i2c_adapter *adap,
> /* special thing in the current firmware:
> when length is zero the read-failed */ len = dib0700_ctrl_rd(d,
> st->buf, msg[i].len + 2,
> - msg[i+1].buf, msg[i+1].len);
> + st->buf, msg[i +
> 1].len); if (len <= 0) {
> deb_info("I2C read failed on address
> 0x%02x\n", msg[i].addr);
> break;
> }
>
> + memcpy(msg[i + 1].buf, st->buf, msg[i +
> 1].len); +
> msg[i+1].len = len;
>
> i++;
> diff --git a/drivers/media/usb/dvb-usb/dib0700_devices.c
> b/drivers/media/usb/dvb-usb/dib0700_devices.c index
> 0857b56e652c..ef1b8ee75c57 100644 ---
> a/drivers/media/usb/dvb-usb/dib0700_devices.c +++
> b/drivers/media/usb/dvb-usb/dib0700_devices.c @@ -508,8 +508,6 @@
> static int stk7700ph_tuner_attach(struct dvb_usb_adapter *adap)
> #define DEFAULT_RC_INTERVAL 50
>
> -static u8 rc_request[] = { REQUEST_POLL_RC, 0 };
> -
> /*
> * This function is used only when firmware is < 1.20 version. Newer
> * firmwares use bulk mode, with functions implemented at
> dib0700_core, @@ -517,7 +515,6 @@ static u8 rc_request[] =
> { REQUEST_POLL_RC, 0 }; */
> static int dib0700_rc_query_old_firmware(struct dvb_usb_device *d)
> {
> - u8 key[4];
> enum rc_type protocol;
> u32 scancode;
> u8 toggle;
> @@ -532,39 +529,43 @@ static int dib0700_rc_query_old_firmware(struct
> dvb_usb_device *d) return 0;
> }
>
> - i = dib0700_ctrl_rd(d, rc_request, 2, key, 4);
> + st->buf[0] = REQUEST_POLL_RC;
> + st->buf[1] = 0;
> +
> + i = dib0700_ctrl_rd(d, st->buf, 2, st->buf, 4);
> if (i <= 0) {
> err("RC Query Failed");
> - return -1;
> + return -EIO;
> }
>
> /* losing half of KEY_0 events from Philipps rc5 remotes.. */
> - if (key[0] == 0 && key[1] == 0 && key[2] == 0 && key[3] == 0)
> + if (st->buf[0] == 0 && st->buf[1] == 0
> + && st->buf[2] == 0 && st->buf[3] == 0)
> return 0;
>
> - /* info("%d: %2X %2X %2X
> %2X",dvb_usb_dib0700_ir_proto,(int)key[3-2],(int)key[3-3],(int)key[3-1],(int)key[3]);
> */
> + /* info("%d: %2X %2X %2X
> %2X",dvb_usb_dib0700_ir_proto,(int)st->buf[3 - 2],(int)st->buf[3 -
> 3],(int)st->buf[3 - 1],(int)st->buf[3]); */ dib0700_rc_setup(d,
> NULL); /* reset ir sensor data to prevent false events */
> switch (d->props.rc.core.protocol) {
> case RC_BIT_NEC:
> /* NEC protocol sends repeat code as 0 0 0 FF */
> - if ((key[3-2] == 0x00) && (key[3-3] == 0x00) &&
> - (key[3] == 0xff)) {
> + if ((st->buf[3 - 2] == 0x00) && (st->buf[3 - 3] ==
> 0x00) &&
> + (st->buf[3] == 0xff)) {
> rc_repeat(d->rc_dev);
> return 0;
> }
>
> protocol = RC_TYPE_NEC;
> - scancode = RC_SCANCODE_NEC(key[3-2], key[3-3]);
> + scancode = RC_SCANCODE_NEC(st->buf[3 - 2], st->buf[3
> - 3]); toggle = 0;
> break;
>
> default:
> /* RC-5 protocol changes toggle bit on new keypress
> */ protocol = RC_TYPE_RC5;
> - scancode = RC_SCANCODE_RC5(key[3-2], key[3-3]);
> - toggle = key[3-1];
> + scancode = RC_SCANCODE_RC5(st->buf[3 - 2], st->buf[3
> - 3]);
> + toggle = st->buf[3 - 1];
> break;
> }
>

Reviewed-By: Patrick Boettcher <patrick.boettcher@xxxxxxxxx>