I wrote: > Concerns: > - The locking is perhaps too complex? Ok, to highlight the benefits of this series, I expect that patches such as [1] and the one inlined below can follow up to clean up ad-hoc i2c locking in drivers. Putting this locking in one place instead of having it spread out in random drivers is a good thing.
PS. the inlined patch has not been tested as I have no hw, it's a proof of concept. Maybe the simplifications can be extended into rtl2832_sdr.c as well? Anyway, please do test this patch on top of the v4 series if you have the hw. Cheers, Peter [1] https://lkml.org/lkml/2016/3/3/932 diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c index 775444898599..fd1f05e9e79a 100644 --- a/drivers/media/dvb-frontends/rtl2832.c +++ b/drivers/media/dvb-frontends/rtl2832.c @@ -158,36 +158,24 @@ static int rtl2832_bulk_write(struct i2c_client *client, unsigned int reg, const void *val, size_t val_count) { struct rtl2832_dev *dev = i2c_get_clientdata(client); - int ret; - i2c_lock_adapter(client->adapter); - ret = regmap_bulk_write(dev->regmap, reg, val, val_count); - i2c_unlock_adapter(client->adapter); - return ret; + return regmap_bulk_write(dev->regmap, reg, val, val_count); } static int rtl2832_update_bits(struct i2c_client *client, unsigned int reg, unsigned int mask, unsigned int val) { struct rtl2832_dev *dev = i2c_get_clientdata(client); - int ret; - i2c_lock_adapter(client->adapter); - ret = regmap_update_bits(dev->regmap, reg, mask, val); - i2c_unlock_adapter(client->adapter); - return ret; + return regmap_update_bits(dev->regmap, reg, mask, val); } static int rtl2832_bulk_read(struct i2c_client *client, unsigned int reg, void *val, size_t val_count) { struct rtl2832_dev *dev = i2c_get_clientdata(client); - int ret; - i2c_lock_adapter(client->adapter); - ret = regmap_bulk_read(dev->regmap, reg, val, val_count); - i2c_unlock_adapter(client->adapter); - return ret; + return regmap_bulk_read(dev->regmap, reg, val, val_count); } static int rtl2832_rd_demod_reg(struct rtl2832_dev *dev, int reg, u32 *val) @@ -204,7 +192,7 @@ static int rtl2832_rd_demod_reg(struct rtl2832_dev *dev, int reg, u32 *val) len = (msb >> 3) + 1; mask = REG_MASK(msb - lsb); - ret = rtl2832_bulk_read(client, reg_start_addr, reading, len); + ret = regmap_bulk_read(dev->regmap, reg_start_addr, reading, len); if (ret) goto err; @@ -234,7 +222,7 @@ static int rtl2832_wr_demod_reg(struct rtl2832_dev *dev, int reg, u32 val) len = (msb >> 3) + 1; mask = REG_MASK(msb - lsb); - ret = rtl2832_bulk_read(client, reg_start_addr, reading, len); + ret = regmap_bulk_read(dev->regmap, reg_start_addr, reading, len); if (ret) goto err; @@ -248,7 +236,7 @@ static int rtl2832_wr_demod_reg(struct rtl2832_dev *dev, int reg, u32 val) for (i = 0; i < len; i++) writing[i] = (writing_tmp >> ((len - 1 - i) * 8)) & 0xff; - ret = rtl2832_bulk_write(client, reg_start_addr, writing, len); + ret = regmap_bulk_write(dev->regmap, reg_start_addr, writing, len); if (ret) goto err; @@ -492,7 +480,7 @@ static int rtl2832_set_frontend(struct dvb_frontend *fe) fe->ops.tuner_ops.set_params(fe); /* PIP mode related */ - ret = rtl2832_bulk_write(client, 0x192, "\x00\x0f\xff", 3); + ret = regmap_bulk_write(dev->regmap, 0x192, "\x00\x0f\xff", 3); if (ret) goto err; @@ -530,7 +518,7 @@ static int rtl2832_set_frontend(struct dvb_frontend *fe) } for (j = 0; j < sizeof(bw_params[0]); j++) { - ret = rtl2832_bulk_write(client, 0x11c + j, &bw_params[i][j], 1); + ret = regmap_bulk_write(dev->regmap, 0x11c + j, &bw_params[i][j], 1); if (ret) goto err; } @@ -586,11 +574,11 @@ static int rtl2832_get_frontend(struct dvb_frontend *fe) if (dev->sleeping) return 0; - ret = rtl2832_bulk_read(client, 0x33c, buf, 2); + ret = regmap_bulk_read(dev->regmap, 0x33c, buf, 2); if (ret) goto err; - ret = rtl2832_bulk_read(client, 0x351, &buf[2], 1); + ret = regmap_bulk_read(dev->regmap, 0x351, &buf[2], 1); if (ret) goto err; @@ -757,7 +745,7 @@ static void rtl2832_stat_work(struct work_struct *work) /* signal strength */ if (dev->fe_status & FE_HAS_SIGNAL) { /* read digital AGC */ - ret = rtl2832_bulk_read(client, 0x305, &u8tmp, 1); + ret = regmap_bulk_read(dev->regmap, 0x305, &u8tmp, 1); if (ret) goto err; @@ -783,7 +771,7 @@ static void rtl2832_stat_work(struct work_struct *work) {87659938, 87659938, 87885178, 88241743}, }; - ret = rtl2832_bulk_read(client, 0x33c, &u8tmp, 1); + ret = regmap_bulk_read(dev->regmap, 0x33c, &u8tmp, 1); if (ret) goto err; @@ -795,7 +783,7 @@ static void rtl2832_stat_work(struct work_struct *work) if (hierarchy > HIERARCHY_NUM - 1) goto err_schedule_delayed_work; - ret = rtl2832_bulk_read(client, 0x40c, buf, 2); + ret = regmap_bulk_read(dev->regmap, 0x40c, buf, 2); if (ret) goto err; @@ -816,7 +804,7 @@ static void rtl2832_stat_work(struct work_struct *work) /* BER */ if (dev->fe_status & FE_HAS_LOCK) { - ret = rtl2832_bulk_read(client, 0x34e, buf, 2); + ret = regmap_bulk_read(dev->regmap, 0x34e, buf, 2); if (ret) goto err; @@ -844,8 +832,6 @@ err: /* * I2C gate/mux/repeater logic - * We must use unlocked __i2c_transfer() here (through regmap) because of I2C - * adapter lock is already taken by tuner driver. * There is delay mechanism to avoid unneeded I2C gate open / close. Gate close * is delayed here a little bit in order to see if there is sequence of I2C * messages sent to same I2C bus. @@ -857,7 +843,7 @@ static void rtl2832_i2c_gate_work(struct work_struct *work) int ret; /* close gate */ - ret = rtl2832_update_bits(dev->client, 0x101, 0x08, 0x00); + ret = regmap_update_bits(dev->regmap, 0x101, 0x08, 0x00); if (ret) goto err; @@ -875,10 +861,7 @@ static int rtl2832_select(struct i2c_mux_core *muxc, u32 chan_id) /* terminate possible gate closing */ cancel_delayed_work(&dev->i2c_gate_work); - /* - * I2C adapter lock is already taken and due to that we will use - * regmap_update_bits() which does not lock again I2C adapter. - */ + /* open gate */ ret = regmap_update_bits(dev->regmap, 0x101, 0x08, 0x08); if (ret) goto err; @@ -950,120 +933,6 @@ static bool rtl2832_volatile_reg(struct device *dev, unsigned int reg) return false; } -/* - * We implement own I2C access routines for regmap in order to get manual access - * to I2C adapter lock, which is needed for I2C mux adapter. - */ -static int rtl2832_regmap_read(void *context, const void *reg_buf, - size_t reg_size, void *val_buf, size_t val_size) -{ - struct i2c_client *client = context; - int ret; - struct i2c_msg msg[2] = { - { - .addr = client->addr, - .flags = 0, - .len = reg_size, - .buf = (u8 *)reg_buf, - }, { - .addr = client->addr, - .flags = I2C_M_RD, - .len = val_size, - .buf = val_buf, - } - }; - - ret = __i2c_transfer(client->adapter, msg, 2); - if (ret != 2) { - dev_warn(&client->dev, "i2c reg read failed %d reg %02x\n", - ret, *(u8 *)reg_buf); - if (ret >= 0) - ret = -EREMOTEIO; - return ret; - } - return 0; -} - -static int rtl2832_regmap_write(void *context, const void *data, size_t count) -{ - struct i2c_client *client = context; - int ret; - struct i2c_msg msg[1] = { - { - .addr = client->addr, - .flags = 0, - .len = count, - .buf = (u8 *)data, - } - }; - - ret = __i2c_transfer(client->adapter, msg, 1); - if (ret != 1) { - dev_warn(&client->dev, "i2c reg write failed %d reg %02x\n", - ret, *(u8 *)data); - if (ret >= 0) - ret = -EREMOTEIO; - return ret; - } - return 0; -} - -static int rtl2832_regmap_gather_write(void *context, const void *reg, - size_t reg_len, const void *val, - size_t val_len) -{ - struct i2c_client *client = context; - int ret; - u8 buf[256]; - struct i2c_msg msg[1] = { - { - .addr = client->addr, - .flags = 0, - .len = 1 + val_len, - .buf = buf, - } - }; - - buf[0] = *(u8 const *)reg; - memcpy(&buf[1], val, val_len); - - ret = __i2c_transfer(client->adapter, msg, 1); - if (ret != 1) { - dev_warn(&client->dev, "i2c reg write failed %d reg %02x\n", - ret, *(u8 const *)reg); - if (ret >= 0) - ret = -EREMOTEIO; - return ret; - } - return 0; -} - -/* - * FIXME: Hack. Implement own regmap locking in order to silence lockdep - * recursive lock warning. That happens when regmap I2C client calls I2C mux - * adapter, which leads demod I2C repeater enable via demod regmap. Operation - * takes two regmap locks recursively - but those are different regmap instances - * in a two different I2C drivers, so it is not deadlock. Proper fix is to make - * regmap aware of lockdep. - */ -static void rtl2832_regmap_lock(void *__dev) -{ - struct rtl2832_dev *dev = __dev; - struct i2c_client *client = dev->client; - - dev_dbg(&client->dev, "\n"); - mutex_lock(&dev->regmap_mutex); -} - -static void rtl2832_regmap_unlock(void *__dev) -{ - struct rtl2832_dev *dev = __dev; - struct i2c_client *client = dev->client; - - dev_dbg(&client->dev, "\n"); - mutex_unlock(&dev->regmap_mutex); -} - static struct dvb_frontend *rtl2832_get_dvb_frontend(struct i2c_client *client) { struct rtl2832_dev *dev = i2c_get_clientdata(client); @@ -1087,7 +956,7 @@ static int rtl2832_enable_slave_ts(struct i2c_client *client) dev_dbg(&client->dev, "\n"); - ret = rtl2832_bulk_write(client, 0x10c, "\x5f\xff", 2); + ret = regmap_bulk_write(dev->regmap, 0x10c, "\x5f\xff", 2); if (ret) goto err; @@ -1095,11 +964,11 @@ static int rtl2832_enable_slave_ts(struct i2c_client *client) if (ret) goto err; - ret = rtl2832_bulk_write(client, 0x0bc, "\x18", 1); + ret = regmap_bulk_write(dev->regmap, 0x0bc, "\x18", 1); if (ret) goto err; - ret = rtl2832_bulk_write(client, 0x192, "\x7f\xf7\xff", 3); + ret = regmap_bulk_write(dev->regmap, 0x192, "\x7f\xf7\xff", 3); if (ret) goto err; @@ -1133,7 +1002,7 @@ static int rtl2832_pid_filter_ctrl(struct dvb_frontend *fe, int onoff) else u8tmp = 0x00; - ret = rtl2832_update_bits(client, 0x061, 0xc0, u8tmp); + ret = regmap_update_bits(dev->regmap, 0x061, 0xc0, u8tmp); if (ret) goto err; @@ -1168,14 +1037,14 @@ static int rtl2832_pid_filter(struct dvb_frontend *fe, u8 index, u16 pid, buf[1] = (dev->filters >> 8) & 0xff; buf[2] = (dev->filters >> 16) & 0xff; buf[3] = (dev->filters >> 24) & 0xff; - ret = rtl2832_bulk_write(client, 0x062, buf, 4); + ret = regmap_bulk_write(dev->regmap, 0x062, buf, 4); if (ret) goto err; /* add PID */ buf[0] = (pid >> 8) & 0xff; buf[1] = (pid >> 0) & 0xff; - ret = rtl2832_bulk_write(client, 0x066 + 2 * index, buf, 2); + ret = regmap_bulk_write(dev->regmap, 0x066 + 2 * index, buf, 2); if (ret) goto err; @@ -1193,12 +1062,6 @@ static int rtl2832_probe(struct i2c_client *client, struct rtl2832_dev *dev; int ret; u8 tmp; - static const struct regmap_bus regmap_bus = { - .read = rtl2832_regmap_read, - .write = rtl2832_regmap_write, - .gather_write = rtl2832_regmap_gather_write, - .val_format_endian_default = REGMAP_ENDIAN_NATIVE, - }; static const struct regmap_range_cfg regmap_range_cfg[] = { { .selector_reg = 0x00, @@ -1231,15 +1094,12 @@ static int rtl2832_probe(struct i2c_client *client, mutex_init(&dev->regmap_mutex); dev->regmap_config.reg_bits = 8, dev->regmap_config.val_bits = 8, - dev->regmap_config.lock = rtl2832_regmap_lock, - dev->regmap_config.unlock = rtl2832_regmap_unlock, - dev->regmap_config.lock_arg = dev, dev->regmap_config.volatile_reg = rtl2832_volatile_reg, dev->regmap_config.max_register = 5 * 0x100, dev->regmap_config.ranges = regmap_range_cfg, dev->regmap_config.num_ranges = ARRAY_SIZE(regmap_range_cfg), dev->regmap_config.cache_type = REGCACHE_NONE, - dev->regmap = regmap_init(&client->dev, ®map_bus, client, + dev->regmap = regmap_init(&client->dev, NULL, client, &dev->regmap_config); if (IS_ERR(dev->regmap)) { ret = PTR_ERR(dev->regmap); @@ -1247,12 +1107,13 @@ static int rtl2832_probe(struct i2c_client *client, } /* check if the demod is there */ - ret = rtl2832_bulk_read(client, 0x000, &tmp, 1); + ret = regmap_bulk_read(dev->regmap, 0x000, &tmp, 1); if (ret) goto err_regmap_exit; /* create muxed i2c adapter for demod tuner bus */ - dev->muxc = i2c_mux_one_adapter(i2c, &i2c->dev, 0, 0, 0, 0, 0, + dev->muxc = i2c_mux_one_adapter(i2c, &i2c->dev, 0, + I2C_CONTROLLED_MUX, 0, 0, 0, rtl2832_select, rtl2832_deselect); if (IS_ERR(dev->muxc)) { ret = PTR_ERR(dev->muxc); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
