[media] dtt200u: don't do DMA on stack

The USB control messages require DMA to work. We cannot pass
a stack-allocated buffer, as it is not warranted that the
stack would be into a DMA enabled area.

Reviewed-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/usb/dvb-usb/dtt200u.c b/drivers/media/usb/dvb-usb/dtt200u.c
index d2a01b50af0daf7ce7ab7d17686b845574c291a1..7706938b5167a10556529d6eb208e84ee28a8064 100644 (file)
--- a/drivers/media/usb/dvb-usb/dtt200u.c
+++ b/drivers/media/usb/dvb-usb/dtt200u.c
@@ -20,74 +20,103 @@ MODULE_PARM_DESC(debug, "set debugging level (1=info,xfer=2 (or-able))." DVB_USB
 
 DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
 
+struct dtt200u_state {
+       unsigned char data[80];
+       struct mutex data_mutex;
+};
+
 static int dtt200u_power_ctrl(struct dvb_usb_device *d, int onoff)
 {
-       u8 b = SET_INIT;
+       struct dtt200u_state *st = d->priv;
+
+       mutex_lock(&st->data_mutex);
+
+       st->data[0] = SET_INIT;
 
        if (onoff)
-               dvb_usb_generic_write(d,&b,2);
+               dvb_usb_generic_write(d, st->data, 2);
 
+       mutex_unlock(&st->data_mutex);
        return 0;
 }
 
 static int dtt200u_streaming_ctrl(struct dvb_usb_adapter *adap, int onoff)
 {
-       u8 b_streaming[2] = { SET_STREAMING, onoff };
-       u8 b_rst_pid = RESET_PID_FILTER;
+       struct dtt200u_state *st = adap->dev->priv;
+
+       mutex_lock(&st->data_mutex);
+       st->data[0] = SET_STREAMING;
+       st->data[1] = onoff;
 
-       dvb_usb_generic_write(adap->dev, b_streaming, 2);
+       dvb_usb_generic_write(adap->dev, st->data, 2);
+
+       if (onoff)
+               return 0;
+
+       st->data[0] = RESET_PID_FILTER;
+       dvb_usb_generic_write(adap->dev, st->data, 1);
+
+       mutex_unlock(&st->data_mutex);
 
-       if (onoff == 0)
-               dvb_usb_generic_write(adap->dev, &b_rst_pid, 1);
        return 0;
 }
 
 static int dtt200u_pid_filter(struct dvb_usb_adapter *adap, int index, u16 pid, int onoff)
 {
-       u8 b_pid[4];
+       struct dtt200u_state *st = adap->dev->priv;
+       int ret;
+
        pid = onoff ? pid : 0;
 
-       b_pid[0] = SET_PID_FILTER;
-       b_pid[1] = index;
-       b_pid[2] = pid & 0xff;
-       b_pid[3] = (pid >> 8) & 0x1f;
+       mutex_lock(&st->data_mutex);
+       st->data[0] = SET_PID_FILTER;
+       st->data[1] = index;
+       st->data[2] = pid & 0xff;
+       st->data[3] = (pid >> 8) & 0x1f;
 
-       return dvb_usb_generic_write(adap->dev, b_pid, 4);
+       ret = dvb_usb_generic_write(adap->dev, st->data, 4);
+       mutex_unlock(&st->data_mutex);
+
+       return ret;
 }
 
 static int dtt200u_rc_query(struct dvb_usb_device *d)
 {
-       u8 key[5],cmd = GET_RC_CODE;
+       struct dtt200u_state *st = d->priv;
        u32 scancode;
 
-       dvb_usb_generic_rw(d,&cmd,1,key,5,0);
-       if (key[0] == 1) {
+       mutex_lock(&st->data_mutex);
+       st->data[0] = GET_RC_CODE;
+
+       dvb_usb_generic_rw(d, st->data, 1, st->data, 5, 0);
+       if (st->data[0] == 1) {
                enum rc_type proto = RC_TYPE_NEC;
 
-               scancode = key[1];
-               if ((u8) ~key[1] != key[2]) {
+               scancode = st->data[1];
+               if ((u8) ~st->data[1] != st->data[2]) {
                        /* Extended NEC */
                        scancode = scancode << 8;
-                       scancode |= key[2];
+                       scancode |= st->data[2];
                        proto = RC_TYPE_NECX;
                }
                scancode = scancode << 8;
-               scancode |= key[3];
+               scancode |= st->data[3];
 
                /* Check command checksum is ok */
-               if ((u8) ~key[3] == key[4])
+               if ((u8) ~st->data[3] == st->data[4])
                        rc_keydown(d->rc_dev, proto, scancode, 0);
                else
                        rc_keyup(d->rc_dev);
-       } else if (key[0] == 2) {
+       } else if (st->data[0] == 2) {
                rc_repeat(d->rc_dev);
        } else {
                rc_keyup(d->rc_dev);
        }
 
-       if (key[0] != 0)
-               deb_info("key: %*ph\n", 5, key);
+       if (st->data[0] != 0)
+               deb_info("st->data: %*ph\n", 5, st->data);
 
+       mutex_unlock(&st->data_mutex);
        return 0;
 }
 
@@ -106,17 +135,24 @@ static struct dvb_usb_device_properties wt220u_miglia_properties;
 static int dtt200u_usb_probe(struct usb_interface *intf,
                const struct usb_device_id *id)
 {
+       struct dvb_usb_device *d;
+       struct dtt200u_state *st;
+
        if (0 == dvb_usb_device_init(intf, &dtt200u_properties,
-                                    THIS_MODULE, NULL, adapter_nr) ||
+                                    THIS_MODULE, &d, adapter_nr) ||
            0 == dvb_usb_device_init(intf, &wt220u_properties,
-                                    THIS_MODULE, NULL, adapter_nr) ||
+                                    THIS_MODULE, &d, adapter_nr) ||
            0 == dvb_usb_device_init(intf, &wt220u_fc_properties,
-                                    THIS_MODULE, NULL, adapter_nr) ||
+                                    THIS_MODULE, &d, adapter_nr) ||
            0 == dvb_usb_device_init(intf, &wt220u_zl0353_properties,
-                                    THIS_MODULE, NULL, adapter_nr) ||
+                                    THIS_MODULE, &d, adapter_nr) ||
            0 == dvb_usb_device_init(intf, &wt220u_miglia_properties,
-                                    THIS_MODULE, NULL, adapter_nr))
+                                    THIS_MODULE, &d, adapter_nr)) {
+               st = d->priv;
+               mutex_init(&st->data_mutex);
+
                return 0;
+       }
 
        return -ENODEV;
 }
@@ -140,6 +176,8 @@ static struct dvb_usb_device_properties dtt200u_properties = {
        .usb_ctrl = CYPRESS_FX2,
        .firmware = "dvb-usb-dtt200u-01.fw",
 
+       .size_of_priv     = sizeof(struct dtt200u_state),
+
        .num_adapters = 1,
        .adapter = {
                {
@@ -190,6 +228,8 @@ static struct dvb_usb_device_properties wt220u_properties = {
        .usb_ctrl = CYPRESS_FX2,
        .firmware = "dvb-usb-wt220u-02.fw",
 
+       .size_of_priv     = sizeof(struct dtt200u_state),
+
        .num_adapters = 1,
        .adapter = {
                {
@@ -240,6 +280,8 @@ static struct dvb_usb_device_properties wt220u_fc_properties = {
        .usb_ctrl = CYPRESS_FX2,
        .firmware = "dvb-usb-wt220u-fc03.fw",
 
+       .size_of_priv     = sizeof(struct dtt200u_state),
+
        .num_adapters = 1,
        .adapter = {
                {
@@ -290,6 +332,8 @@ static struct dvb_usb_device_properties wt220u_zl0353_properties = {
        .usb_ctrl = CYPRESS_FX2,
        .firmware = "dvb-usb-wt220u-zl0353-01.fw",
 
+       .size_of_priv     = sizeof(struct dtt200u_state),
+
        .num_adapters = 1,
        .adapter = {
                {
@@ -340,6 +384,8 @@ static struct dvb_usb_device_properties wt220u_miglia_properties = {
        .usb_ctrl = CYPRESS_FX2,
        .firmware = "dvb-usb-wt220u-miglia-01.fw",
 
+       .size_of_priv     = sizeof(struct dtt200u_state),
+
        .num_adapters = 1,
        .generic_bulk_ctrl_endpoint = 0x01,