From 433c4864977a943eabea737f2f0894430795eca3 Mon Sep 17 00:00:00 2001 From: Antti Palosaari Date: Sun, 26 Jul 2015 17:30:07 -0300 Subject: [PATCH] [media] mt2060: add param to split long i2c writes Add configuration parameter to split long i2c writes as some I2C adapters cannot write 10 bytes used as a one go. Signed-off-by: Antti Palosaari Signed-off-by: Mauro Carvalho Chehab --- drivers/media/tuners/mt2060.c | 21 +++++++++++++++++---- drivers/media/tuners/mt2060.h | 3 +++ drivers/media/tuners/mt2060_priv.h | 1 + 3 files changed, 21 insertions(+), 4 deletions(-) diff --git a/drivers/media/tuners/mt2060.c b/drivers/media/tuners/mt2060.c index b8acfa2..14f5935 100644 --- a/drivers/media/tuners/mt2060.c +++ b/drivers/media/tuners/mt2060.c @@ -67,13 +67,24 @@ static int mt2060_writereg(struct mt2060_priv *priv, u8 reg, u8 val) // Writes a set of consecutive registers static int mt2060_writeregs(struct mt2060_priv *priv,u8 *buf, u8 len) { + int rem, val_len; + u8 xfer_buf[16]; struct i2c_msg msg = { - .addr = priv->cfg->i2c_address, .flags = 0, .buf = buf, .len = len + .addr = priv->cfg->i2c_address, .flags = 0, .buf = xfer_buf }; - if (i2c_transfer(priv->i2c, &msg, 1) != 1) { - printk(KERN_WARNING "mt2060 I2C write failed (len=%i)\n",(int)len); - return -EREMOTEIO; + + for (rem = len - 1; rem > 0; rem -= priv->i2c_max_regs) { + val_len = min_t(int, rem, priv->i2c_max_regs); + msg.len = 1 + val_len; + xfer_buf[0] = buf[0] + len - 1 - rem; + memcpy(&xfer_buf[1], &buf[1 + len - 1 - rem], val_len); + + if (i2c_transfer(priv->i2c, &msg, 1) != 1) { + printk(KERN_WARNING "mt2060 I2C write failed (len=%i)\n", val_len); + return -EREMOTEIO; + } } + return 0; } @@ -365,6 +376,7 @@ struct dvb_frontend * mt2060_attach(struct dvb_frontend *fe, struct i2c_adapter priv->cfg = cfg; priv->i2c = i2c; priv->if1_freq = if1; + priv->i2c_max_regs = ~0; if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */ @@ -422,6 +434,7 @@ static int mt2060_probe(struct i2c_client *client, dev->i2c = client->adapter; dev->if1_freq = pdata->if1 ? pdata->if1 : 1220; dev->client = client; + dev->i2c_max_regs = pdata->i2c_write_max ? pdata->i2c_write_max - 1 : ~0; ret = mt2060_readreg(dev, REG_PART_REV, &chip_id); if (ret) { diff --git a/drivers/media/tuners/mt2060.h b/drivers/media/tuners/mt2060.h index 41feb2c..cc534eb 100644 --- a/drivers/media/tuners/mt2060.h +++ b/drivers/media/tuners/mt2060.h @@ -30,12 +30,15 @@ struct i2c_adapter; * struct mt2060_platform_data - Platform data for the mt2060 driver * @clock_out: Clock output setting. 0 = off, 1 = CLK/4, 2 = CLK/2, 3 = CLK/1. * @if1: First IF used [MHz]. 0 defaults to 1220. + * @i2c_write_max: Maximum number of bytes I2C adapter can write at once. + * 0 defaults to maximum. * @dvb_frontend: DVB frontend. */ struct mt2060_platform_data { u8 clock_out; u16 if1; + unsigned int i2c_write_max:5; struct dvb_frontend *dvb_frontend; }; diff --git a/drivers/media/tuners/mt2060_priv.h b/drivers/media/tuners/mt2060_priv.h index af677b2..cc738aa 100644 --- a/drivers/media/tuners/mt2060_priv.h +++ b/drivers/media/tuners/mt2060_priv.h @@ -94,6 +94,7 @@ struct mt2060_priv { struct i2c_client *client; struct mt2060_config config; + u8 i2c_max_regs; u32 frequency; u16 if1_freq; u8 fmfreq; -- 2.7.4