diff options
| author | Hans de Goede | 2016-01-14 14:06:25 +0100 |
|---|---|---|
| committer | Heiko Schocher | 2016-01-21 07:23:29 +0100 |
| commit | 904dfbfd67fbdf4562236efb3f0769ecfe7a7e58 (patch) | |
| tree | 90985ef4a967982921cc18233c9f2e4deb59f71e | |
| parent | 57e5ecaf755d5301cd33683788e4b8432938bbbe (diff) | |
i2c: mvtwsi: Fix mvtwsi not working on sun6i and newer sunxi SoCs
On sun6i and newer IFLG is a write-clear bit which is cleared by writing 1,
rather then a normal r/w bit which is cleared by writing 0.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
applied with fixing 3 checkpatch warnings
in drivers/i2c/mvtwsi.c:
WARNING: line over 80 characters
ERROR: code indent should use tabs where possible
WARNING: please, no spaces at the start of a line
Signed-off-by: Heiko Schocher <hs@denx.de>
| -rw-r--r-- | drivers/i2c/mvtwsi.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/drivers/i2c/mvtwsi.c b/drivers/i2c/mvtwsi.c index 5dc4fbba1fe..30a5b11f9f3 100644 --- a/drivers/i2c/mvtwsi.c +++ b/drivers/i2c/mvtwsi.c @@ -73,6 +73,17 @@ struct mvtwsi_registers { #define MVTWSI_CONTROL_INTEN 0x00000080 /* + * On sun6i and newer IFLG is a write-clear bit which is cleared by writing 1, + * on other platforms it is a normal r/w bit which is cleared by writing 0. + */ + +#ifdef CONFIG_SUNXI_GEN_SUN6I +#define MVTWSI_CONTROL_CLEAR_IFLG 0x00000008 +#else +#define MVTWSI_CONTROL_CLEAR_IFLG 0x00000000 +#endif + +/* * Status register values -- only those expected in normal master * operation on non-10-bit-address devices; whatever status we don't * expect in nominal conditions (bus errors, arbitration losses, @@ -189,7 +200,8 @@ static int twsi_start(struct i2c_adapter *adap, int expected_status) /* globally set TWSIEN in case it was not */ twsi_control_flags |= MVTWSI_CONTROL_TWSIEN; /* assert START */ - writel(twsi_control_flags | MVTWSI_CONTROL_START, &twsi->control); + twsi_control_flags |= MVTWSI_CONTROL_START | MVTWSI_CONTROL_CLEAR_IFLG; + writel(twsi_control_flags, &twsi->control); /* wait for controller to process START */ return twsi_wait(adap, expected_status); } @@ -204,7 +216,7 @@ static int twsi_send(struct i2c_adapter *adap, u8 byte, int expected_status) /* put byte in data register for sending */ writel(byte, &twsi->data); /* clear any pending interrupt -- that'll cause sending */ - writel(twsi_control_flags, &twsi->control); + writel(twsi_control_flags | MVTWSI_CONTROL_CLEAR_IFLG, &twsi->control); /* wait for controller to receive byte and check ACK */ return twsi_wait(adap, expected_status); } @@ -224,7 +236,7 @@ static int twsi_recv(struct i2c_adapter *adap, u8 *byte) else expected_status = MVTWSI_STATUS_DATA_R_NAK; /* acknowledge *previous state* and launch receive */ - writel(twsi_control_flags, &twsi->control); + writel(twsi_control_flags | MVTWSI_CONTROL_CLEAR_IFLG, &twsi->control); /* wait for controller to receive byte and assert ACK or NAK */ status = twsi_wait(adap, expected_status); /* if we did receive expected byte then store it */ @@ -246,7 +258,7 @@ static int twsi_stop(struct i2c_adapter *adap, int status) /* assert STOP */ control = MVTWSI_CONTROL_TWSIEN | MVTWSI_CONTROL_STOP; - writel(control, &twsi->control); + writel(control | MVTWSI_CONTROL_CLEAR_IFLG, &twsi->control); /* wait for IDLE; IFLG won't rise so twsi_wait() is no use. */ do { stop_status = readl(&twsi->status); |