[PATCH 0/2] powerpc: i2c-mpc: make I2C bus speed configurable
Wolfgang Grandegger
wg at grandegger.com
Tue Mar 31 23:50:28 EST 2009
Following (most of) Grant's suggestions to my RFC:
http://ozlabs.org/pipermail/linuxppc-dev/2009-March/069820.html
this new patch series now uses:
- the I2c node property "fsl,preserve-clocking" to overtake the
clock settings from the boot loader. The first patch provides this
feature and can be applied *without* delay. This rest will take
more time and discussion, I'm afraid :-( .
- the OF match table to define the I2C clock properties, especially
the source clock pre-scaler:
static const struct of_device_id mpc_i2c_of_match[] = {
{.compatible = "fsl,mpc5200b-i2c",
.data = (void *)FSL_I2C_DEV_CLOCK_5200, },
{.compatible = "fsl,mpc5200-i2c",
.data = (void *)FSL_I2C_DEV_CLOCK_5200, },
{.compatible = "fsl,mpc8313-i2c",
.data = (void *)FSL_I2C_DEV_SEPARATE_DFSRR, },
{.compatible = "fsl,mpc8543-i2c",
.data = (void *)(FSL_I2C_DEV_SEPARATE_DFSRR |
FSL_I2C_DEV_CLOCK_DIV2), },
{.compatible = "fsl,mpc8544-i2c",
.data = (void *)(FSL_I2C_DEV_SEPARATE_DFSRR |
FSL_I2C_DEV_CLOCK_DIV23), },
/* Backward compatibility */
{.compatible = "fsl-i2c", },
{},
};
The "data" field defines the relevant I2C flags.
- arch-specific tables and functions to get the proper Freqency
Divider Register (fdr). I added them to sysdev/fsl_soc.c for
the MPC8xxx and to platforms/52xx/mpc52xx_common.c for the
MPC52xx. This also solves the problem with arch-specific
functions, e.g. for getting the bus frequency.
- dev_dbg() and dev_info() to profit from a more descriptive output.
Hope this solution is OK now?
Thanks,
Wolfgang.
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