[media] DiBxxxx: get rid of DMA buffer on stack
This patch removes the remaining on-stack buffer for USB DMA transfer.
This patch also reduces the stack memory usage.
Cc: stable@kernel.org
Cc: Florian Mickler <florian@mickler.org>
Signed-off-by: Olivier Grenie <olivier.grenie@dibcom.fr>
Signed-off-by: Patrick Boettcher <patrick.boettcher@dibcom.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/dvb/frontends/dibx000_common.c b/drivers/media/dvb/frontends/dibx000_common.c
index f6938f97..dc5d17a 100644
--- a/drivers/media/dvb/frontends/dibx000_common.c
+++ b/drivers/media/dvb/frontends/dibx000_common.c
@@ -10,30 +10,39 @@
static int dibx000_write_word(struct dibx000_i2c_master *mst, u16 reg, u16 val)
{
- u8 b[4] = {
- (reg >> 8) & 0xff, reg & 0xff,
- (val >> 8) & 0xff, val & 0xff,
- };
- struct i2c_msg msg = {
- .addr = mst->i2c_addr,.flags = 0,.buf = b,.len = 4
- };
+ mst->i2c_write_buffer[0] = (reg >> 8) & 0xff;
+ mst->i2c_write_buffer[1] = reg & 0xff;
+ mst->i2c_write_buffer[2] = (val >> 8) & 0xff;
+ mst->i2c_write_buffer[3] = val & 0xff;
- return i2c_transfer(mst->i2c_adap, &msg, 1) != 1 ? -EREMOTEIO : 0;
+ memset(mst->msg, 0, sizeof(struct i2c_msg));
+ mst->msg[0].addr = mst->i2c_addr;
+ mst->msg[0].flags = 0;
+ mst->msg[0].buf = mst->i2c_write_buffer;
+ mst->msg[0].len = 4;
+
+ return i2c_transfer(mst->i2c_adap, mst->msg, 1) != 1 ? -EREMOTEIO : 0;
}
static u16 dibx000_read_word(struct dibx000_i2c_master *mst, u16 reg)
{
- u8 wb[2] = { reg >> 8, reg & 0xff };
- u8 rb[2];
- struct i2c_msg msg[2] = {
- {.addr = mst->i2c_addr, .flags = 0, .buf = wb, .len = 2},
- {.addr = mst->i2c_addr, .flags = I2C_M_RD, .buf = rb, .len = 2},
- };
+ mst->i2c_write_buffer[0] = reg >> 8;
+ mst->i2c_write_buffer[1] = reg & 0xff;
- if (i2c_transfer(mst->i2c_adap, msg, 2) != 2)
+ memset(mst->msg, 0, 2 * sizeof(struct i2c_msg));
+ mst->msg[0].addr = mst->i2c_addr;
+ mst->msg[0].flags = 0;
+ mst->msg[0].buf = mst->i2c_write_buffer;
+ mst->msg[0].len = 2;
+ mst->msg[1].addr = mst->i2c_addr;
+ mst->msg[1].flags = I2C_M_RD;
+ mst->msg[1].buf = mst->i2c_read_buffer;
+ mst->msg[1].len = 2;
+
+ if (i2c_transfer(mst->i2c_adap, mst->msg, 2) != 2)
dprintk("i2c read error on %d", reg);
- return (rb[0] << 8) | rb[1];
+ return (mst->i2c_read_buffer[0] << 8) | mst->i2c_read_buffer[1];
}
static int dibx000_is_i2c_done(struct dibx000_i2c_master *mst)
@@ -248,26 +257,32 @@
struct i2c_msg msg[], int num)
{
struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
- struct i2c_msg m[2 + num];
- u8 tx_open[4], tx_close[4];
- memset(m, 0, sizeof(struct i2c_msg) * (2 + num));
+ if (num > 32) {
+ dprintk("%s: too much I2C message to be transmitted (%i).\
+ Maximum is 32", __func__, num);
+ return -ENOMEM;
+ }
+
+ memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));
dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_6_7);
- dibx000_i2c_gate_ctrl(mst, tx_open, msg[0].addr, 1);
- m[0].addr = mst->i2c_addr;
- m[0].buf = tx_open;
- m[0].len = 4;
+ /* open the gate */
+ dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
+ mst->msg[0].addr = mst->i2c_addr;
+ mst->msg[0].buf = &mst->i2c_write_buffer[0];
+ mst->msg[0].len = 4;
- memcpy(&m[1], msg, sizeof(struct i2c_msg) * num);
+ memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);
- dibx000_i2c_gate_ctrl(mst, tx_close, 0, 0);
- m[num + 1].addr = mst->i2c_addr;
- m[num + 1].buf = tx_close;
- m[num + 1].len = 4;
+ /* close the gate */
+ dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
+ mst->msg[num + 1].addr = mst->i2c_addr;
+ mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
+ mst->msg[num + 1].len = 4;
- return i2c_transfer(mst->i2c_adap, m, 2 + num) == 2 + num ? num : -EIO;
+ return i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ? num : -EIO;
}
static struct i2c_algorithm dibx000_i2c_gated_gpio67_algo = {
@@ -279,26 +294,32 @@
struct i2c_msg msg[], int num)
{
struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
- struct i2c_msg m[2 + num];
- u8 tx_open[4], tx_close[4];
- memset(m, 0, sizeof(struct i2c_msg) * (2 + num));
+ if (num > 32) {
+ dprintk("%s: too much I2C message to be transmitted (%i).\
+ Maximum is 32", __func__, num);
+ return -ENOMEM;
+ }
+
+ memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));
dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
- dibx000_i2c_gate_ctrl(mst, tx_open, msg[0].addr, 1);
- m[0].addr = mst->i2c_addr;
- m[0].buf = tx_open;
- m[0].len = 4;
+ /* open the gate */
+ dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
+ mst->msg[0].addr = mst->i2c_addr;
+ mst->msg[0].buf = &mst->i2c_write_buffer[0];
+ mst->msg[0].len = 4;
- memcpy(&m[1], msg, sizeof(struct i2c_msg) * num);
+ memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);
- dibx000_i2c_gate_ctrl(mst, tx_close, 0, 0);
- m[num + 1].addr = mst->i2c_addr;
- m[num + 1].buf = tx_close;
- m[num + 1].len = 4;
+ /* close the gate */
+ dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
+ mst->msg[num + 1].addr = mst->i2c_addr;
+ mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
+ mst->msg[num + 1].len = 4;
- return i2c_transfer(mst->i2c_adap, m, 2 + num) == 2 + num ? num : -EIO;
+ return i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ? num : -EIO;
}
static struct i2c_algorithm dibx000_i2c_gated_tuner_algo = {