diff options
| author | Stefan Mavrodiev | 2018-02-13 09:27:40 +0200 |
|---|---|---|
| committer | Heiko Schocher | 2018-02-19 08:21:38 +0100 |
| commit | 004b4cdaeca45d4702f0494f517b6fc472ccf4a1 (patch) | |
| tree | 20fe7b54a167010128620c830f18033ed8e223fb /drivers/i2c/mvtwsi.c | |
| parent | 02b0895c215e252cff50d9edf53a972d2bbbfd30 (diff) | |
i2c: mvtwsi.c: Fix set speed
Previous patch for this driver breaks i2c initialization.
commit 8bcf12ccce89 ("i2c: mvtwsi.c: Avoid NULL dereference")
If actual_speed is passed as NULL in this function:
static void __twsi_i2c_init(struct mvtwsi_registers *twsi, int speed,
int slaveadd, uint *actual_speed)
than __twsi_i2c_set_bus_speed never get called. This causes i2c clock
to run on default speed - 2MHz (measured with oscilloscope). This is issue
on some boards, sunxi for example, since on I2C0 bus PMU is connected.
The bootlogs with and without the patch are as follows:
Wihtout the patch:
U-Boot SPL 2018.03-rc2 (Feb 13 2018 - 09:23:17 +0200)
DRAM: 1024 MiB
Failed to set core voltage! Can't set CPU frequency
Trying to boot from FEL
U-Boot 2018.03-rc2 (Feb 13 2018 - 09:23:17 +0200) Allwinner Technology
CPU: Allwinner A20 (SUN7I)
Model: Olimex A20-OLinuXino-LIME2
I2C: ready
DRAM: 1 GiB
MMC: SUNXI SD/MMC: 0
With the patch:
U-Boot SPL 2018.03-rc2-00001-g838ff85 (Feb 13 2018 - 09:24:34 +0200)
DRAM: 1024 MiB
CPU: 912000000Hz, AXI/AHB/APB: 3/2/2
Trying to boot from FEL
U-Boot 2018.03-rc2-00001-g838ff85 (Feb 13 2018 - 09:24:34 +0200) Allwinner Technology
CPU: Allwinner A20 (SUN7I)
Model: Olimex A20-OLinuXino-LIME2
I2C: ready
DRAM: 1 GiB
MMC: SUNXI SD/MMC: 0
Signed-off-by: Stefan Mavrodiev <stefan@olimex.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Diffstat (limited to 'drivers/i2c/mvtwsi.c')
| -rw-r--r-- | drivers/i2c/mvtwsi.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/i2c/mvtwsi.c b/drivers/i2c/mvtwsi.c index 30bee0d52e5..38bca897458 100644 --- a/drivers/i2c/mvtwsi.c +++ b/drivers/i2c/mvtwsi.c @@ -487,11 +487,14 @@ static uint __twsi_i2c_set_bus_speed(struct mvtwsi_registers *twsi, static void __twsi_i2c_init(struct mvtwsi_registers *twsi, int speed, int slaveadd, uint *actual_speed) { + uint tmp_speed; + /* Reset controller */ twsi_reset(twsi); /* Set speed */ + tmp_speed = __twsi_i2c_set_bus_speed(twsi, speed); if (actual_speed) - *actual_speed = __twsi_i2c_set_bus_speed(twsi, speed); + *actual_speed = tmp_speed; /* Set slave address; even though we don't use it */ writel(slaveadd, &twsi->slave_address); writel(0, &twsi->xtnd_slave_addr); |