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| author | Marek Vasut <marex@denx.de> | 2012-11-12 14:34:28 +0000 |
|---|---|---|
| committer | Tom Rini <trini@ti.com> | 2012-12-11 13:17:30 -0700 |
| commit | f32a470ed3dfff493473bc25c7d0a01920507eed (patch) | |
| tree | aab877c32ae2e4c9cd0e0252d58c18365cb06a2e /drivers/i2c | |
| parent | 06afa388b2f6f0f974a9d60f0e5fc273b857bdeb (diff) | |
| download | talos-obmc-uboot-f32a470ed3dfff493473bc25c7d0a01920507eed.tar.gz talos-obmc-uboot-f32a470ed3dfff493473bc25c7d0a01920507eed.zip | |
i2c: mxs: Abstract out the MXS I2C speed setup
This patch pulls out the I2C speed setup from the i2c_init() call
and implements the bus configuration lookup table with register
values that needs to be programmed into the I2C IP to run at
particular speed.
This patch is a first step towards implementing run-time I2C bus
speed configuration for the MXS I2C IP.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/mxs_i2c.c | 57 |
1 files changed, 37 insertions, 20 deletions
diff --git a/drivers/i2c/mxs_i2c.c b/drivers/i2c/mxs_i2c.c index 2a193c220d..98f6e8c3d8 100644 --- a/drivers/i2c/mxs_i2c.c +++ b/drivers/i2c/mxs_i2c.c @@ -210,34 +210,51 @@ int i2c_probe(uchar chip) return ret; } +static struct mxs_i2c_speed_table { + uint32_t speed; + uint32_t timing0; + uint32_t timing1; +} mxs_i2c_tbl[] = { + { + 100000, + (0x0078 << I2C_TIMING0_HIGH_COUNT_OFFSET) | + (0x0030 << I2C_TIMING0_RCV_COUNT_OFFSET), + (0x0080 << I2C_TIMING1_LOW_COUNT_OFFSET) | + (0x0030 << I2C_TIMING1_XMIT_COUNT_OFFSET) + }, + { + 400000, + (0x000f << I2C_TIMING0_HIGH_COUNT_OFFSET) | + (0x0007 << I2C_TIMING0_RCV_COUNT_OFFSET), + (0x001f << I2C_TIMING1_LOW_COUNT_OFFSET) | + (0x000f << I2C_TIMING1_XMIT_COUNT_OFFSET), + } +}; + +static struct mxs_i2c_speed_table *mxs_i2c_speed_to_cfg(uint32_t speed) +{ + int i; + for (i = 0; i < ARRAY_SIZE(mxs_i2c_tbl); i++) + if (mxs_i2c_tbl[i].speed == speed) + return &mxs_i2c_tbl[i]; + return NULL; +} + void i2c_init(int speed, int slaveadd) { struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE; + struct mxs_i2c_speed_table *spd = mxs_i2c_speed_to_cfg(speed); - mxs_i2c_reset(); - - switch (speed) { - case 100000: - writel((0x0078 << I2C_TIMING0_HIGH_COUNT_OFFSET) | - (0x0030 << I2C_TIMING0_RCV_COUNT_OFFSET), - &i2c_regs->hw_i2c_timing0); - writel((0x0080 << I2C_TIMING1_LOW_COUNT_OFFSET) | - (0x0030 << I2C_TIMING1_XMIT_COUNT_OFFSET), - &i2c_regs->hw_i2c_timing1); - break; - case 400000: - writel((0x000f << I2C_TIMING0_HIGH_COUNT_OFFSET) | - (0x0007 << I2C_TIMING0_RCV_COUNT_OFFSET), - &i2c_regs->hw_i2c_timing0); - writel((0x001f << I2C_TIMING1_LOW_COUNT_OFFSET) | - (0x000f << I2C_TIMING1_XMIT_COUNT_OFFSET), - &i2c_regs->hw_i2c_timing1); - break; - default: + if (!spd) { printf("MXS I2C: Invalid speed selected (%d Hz)\n", speed); return; } + mxs_i2c_reset(); + + writel(spd->timing0, &i2c_regs->hw_i2c_timing0); + writel(spd->timing1, &i2c_regs->hw_i2c_timing1); + writel((0x0015 << I2C_TIMING2_BUS_FREE_OFFSET) | (0x000d << I2C_TIMING2_LEADIN_COUNT_OFFSET), &i2c_regs->hw_i2c_timing2); |
