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author | Olivier Grenie <olivier.grenie@dibcom.fr> | 2011-05-03 15:27:33 (GMT) |
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committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2011-05-20 12:30:52 (GMT) |
commit | 5a0deeed5741117ee8625d6305d0034e219f102c (patch) | |
tree | 2073570031d4ea19d0acacd5248f8e425fb019fa /drivers/media/dvb/frontends/dib7000p.c | |
parent | 027e99abbfdcca2ed46dfe4ea27c7cc253648cef (diff) | |
download | linux-fsl-qoriq-5a0deeed5741117ee8625d6305d0034e219f102c.tar.xz |
[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>
Diffstat (limited to 'drivers/media/dvb/frontends/dib7000p.c')
-rw-r--r-- | drivers/media/dvb/frontends/dib7000p.c | 72 |
1 files changed, 52 insertions, 20 deletions
diff --git a/drivers/media/dvb/frontends/dib7000p.c b/drivers/media/dvb/frontends/dib7000p.c index 900af60..0c9f40c 100644 --- a/drivers/media/dvb/frontends/dib7000p.c +++ b/drivers/media/dvb/frontends/dib7000p.c @@ -63,6 +63,11 @@ struct dib7000p_state { u16 tuner_enable; struct i2c_adapter dib7090_tuner_adap; + + /* for the I2C transfer */ + struct i2c_msg msg[2]; + u8 i2c_write_buffer[4]; + u8 i2c_read_buffer[2]; }; enum dib7000p_power_mode { @@ -76,29 +81,39 @@ static int dib7090_set_diversity_in(struct dvb_frontend *fe, int onoff); static u16 dib7000p_read_word(struct dib7000p_state *state, u16 reg) { - u8 wb[2] = { reg >> 8, reg & 0xff }; - u8 rb[2]; - struct i2c_msg msg[2] = { - {.addr = state->i2c_addr >> 1, .flags = 0, .buf = wb, .len = 2}, - {.addr = state->i2c_addr >> 1, .flags = I2C_M_RD, .buf = rb, .len = 2}, - }; + state->i2c_write_buffer[0] = reg >> 8; + state->i2c_write_buffer[1] = reg & 0xff; + + memset(state->msg, 0, 2 * sizeof(struct i2c_msg)); + state->msg[0].addr = state->i2c_addr >> 1; + state->msg[0].flags = 0; + state->msg[0].buf = state->i2c_write_buffer; + state->msg[0].len = 2; + state->msg[1].addr = state->i2c_addr >> 1; + state->msg[1].flags = I2C_M_RD; + state->msg[1].buf = state->i2c_read_buffer; + state->msg[1].len = 2; - if (i2c_transfer(state->i2c_adap, msg, 2) != 2) + if (i2c_transfer(state->i2c_adap, state->msg, 2) != 2) dprintk("i2c read error on %d", reg); - return (rb[0] << 8) | rb[1]; + return (state->i2c_read_buffer[0] << 8) | state->i2c_read_buffer[1]; } static int dib7000p_write_word(struct dib7000p_state *state, u16 reg, u16 val) { - u8 b[4] = { - (reg >> 8) & 0xff, reg & 0xff, - (val >> 8) & 0xff, val & 0xff, - }; - struct i2c_msg msg = { - .addr = state->i2c_addr >> 1, .flags = 0, .buf = b, .len = 4 - }; - return i2c_transfer(state->i2c_adap, &msg, 1) != 1 ? -EREMOTEIO : 0; + state->i2c_write_buffer[0] = (reg >> 8) & 0xff; + state->i2c_write_buffer[1] = reg & 0xff; + state->i2c_write_buffer[2] = (val >> 8) & 0xff; + state->i2c_write_buffer[3] = val & 0xff; + + memset(&state->msg[0], 0, sizeof(struct i2c_msg)); + state->msg[0].addr = state->i2c_addr >> 1; + state->msg[0].flags = 0; + state->msg[0].buf = state->i2c_write_buffer; + state->msg[0].len = 4; + + return i2c_transfer(state->i2c_adap, state->msg, 1) != 1 ? -EREMOTEIO : 0; } static void dib7000p_write_tab(struct dib7000p_state *state, u16 * buf) @@ -1550,11 +1565,24 @@ static void dib7000p_release(struct dvb_frontend *demod) int dib7000pc_detection(struct i2c_adapter *i2c_adap) { - u8 tx[2], rx[2]; + u8 *tx, *rx; struct i2c_msg msg[2] = { - {.addr = 18 >> 1, .flags = 0, .buf = tx, .len = 2}, - {.addr = 18 >> 1, .flags = I2C_M_RD, .buf = rx, .len = 2}, + {.addr = 18 >> 1, .flags = 0, .len = 2}, + {.addr = 18 >> 1, .flags = I2C_M_RD, .len = 2}, }; + int ret = 0; + + tx = kzalloc(2*sizeof(u8), GFP_KERNEL); + if (!tx) + return -ENOMEM; + rx = kzalloc(2*sizeof(u8), GFP_KERNEL); + if (!rx) { + goto rx_memory_error; + ret = -ENOMEM; + } + + msg[0].buf = tx; + msg[1].buf = rx; tx[0] = 0x03; tx[1] = 0x00; @@ -1574,7 +1602,11 @@ int dib7000pc_detection(struct i2c_adapter *i2c_adap) } dprintk("-D- DiB7000PC not detected"); - return 0; + + kfree(rx); +rx_memory_error: + kfree(tx); + return ret; } EXPORT_SYMBOL(dib7000pc_detection); |