From 4d2ae8d3b315fbf36d760fd8dd755fb1d55a0f87 Mon Sep 17 00:00:00 2001 From: Patrick Boettcher Date: Wed, 3 Aug 2011 12:08:21 -0300 Subject: DiBcom: protect the I2C bufer access commit 79fcce3230b140f7675f8529ee53fe2f9644f902 upstream. This patch protects the I2C buffer access in order to manage concurrent access. This protection is done using mutex. Furthermore, for the dib9000, if a pid filtering command is received during the tuning, this pid filtering command is delayed to avoid any concurrent access issue. Cc: Mauro Carvalho Chehab Cc: Florian Mickler Signed-off-by: Olivier Grenie Signed-off-by: Patrick Boettcher Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/dvb/frontends/dib7000p.c | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) (limited to 'drivers/media/dvb/frontends/dib7000p.c') diff --git a/drivers/media/dvb/frontends/dib7000p.c b/drivers/media/dvb/frontends/dib7000p.c index 0c9f40c..292bc19 100644 --- a/drivers/media/dvb/frontends/dib7000p.c +++ b/drivers/media/dvb/frontends/dib7000p.c @@ -10,6 +10,7 @@ #include #include #include +#include #include "dvb_math.h" #include "dvb_frontend.h" @@ -68,6 +69,7 @@ struct dib7000p_state { struct i2c_msg msg[2]; u8 i2c_write_buffer[4]; u8 i2c_read_buffer[2]; + struct mutex i2c_buffer_lock; }; enum dib7000p_power_mode { @@ -81,6 +83,13 @@ static int dib7090_set_diversity_in(struct dvb_frontend *fe, int onoff); static u16 dib7000p_read_word(struct dib7000p_state *state, u16 reg) { + u16 ret; + + if (mutex_lock_interruptible(&state->i2c_buffer_lock) < 0) { + dprintk("could not acquire lock"); + return 0; + } + state->i2c_write_buffer[0] = reg >> 8; state->i2c_write_buffer[1] = reg & 0xff; @@ -97,11 +106,20 @@ static u16 dib7000p_read_word(struct dib7000p_state *state, u16 reg) if (i2c_transfer(state->i2c_adap, state->msg, 2) != 2) dprintk("i2c read error on %d", reg); - return (state->i2c_read_buffer[0] << 8) | state->i2c_read_buffer[1]; + ret = (state->i2c_read_buffer[0] << 8) | state->i2c_read_buffer[1]; + mutex_unlock(&state->i2c_buffer_lock); + return ret; } static int dib7000p_write_word(struct dib7000p_state *state, u16 reg, u16 val) { + int ret; + + if (mutex_lock_interruptible(&state->i2c_buffer_lock) < 0) { + dprintk("could not acquire lock"); + return -EINVAL; + } + state->i2c_write_buffer[0] = (reg >> 8) & 0xff; state->i2c_write_buffer[1] = reg & 0xff; state->i2c_write_buffer[2] = (val >> 8) & 0xff; @@ -113,7 +131,10 @@ static int dib7000p_write_word(struct dib7000p_state *state, u16 reg, u16 val) 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; + ret = (i2c_transfer(state->i2c_adap, state->msg, 1) != 1 ? + -EREMOTEIO : 0); + mutex_unlock(&state->i2c_buffer_lock); + return ret; } static void dib7000p_write_tab(struct dib7000p_state *state, u16 * buf) @@ -1646,6 +1667,7 @@ int dib7000p_i2c_enumeration(struct i2c_adapter *i2c, int no_of_demods, u8 defau return -ENOMEM; dpst->i2c_adap = i2c; + mutex_init(&dpst->i2c_buffer_lock); for (k = no_of_demods - 1; k >= 0; k--) { dpst->cfg = cfg[k]; @@ -2324,6 +2346,7 @@ struct dvb_frontend *dib7000p_attach(struct i2c_adapter *i2c_adap, u8 i2c_addr, demod = &st->demod; demod->demodulator_priv = st; memcpy(&st->demod.ops, &dib7000p_ops, sizeof(struct dvb_frontend_ops)); + mutex_init(&st->i2c_buffer_lock); dib7000p_write_word(st, 1287, 0x0003); /* sram lead in, rdy */ @@ -2333,8 +2356,9 @@ struct dvb_frontend *dib7000p_attach(struct i2c_adapter *i2c_adap, u8 i2c_addr, st->version = dib7000p_read_word(st, 897); /* FIXME: make sure the dev.parent field is initialized, or else - request_firmware() will hit an OOPS (this should be moved somewhere - more common) */ + request_firmware() will hit an OOPS (this should be moved somewhere + more common) */ + st->i2c_master.gated_tuner_i2c_adap.dev.parent = i2c_adap->dev.parent; dibx000_init_i2c_master(&st->i2c_master, DIB7000P, st->i2c_adap, st->i2c_addr); -- cgit v1.1