diff options
| author | Ranjani Vaidyanathan <ra5478@freescale.com> | 2012-10-25 15:51:51 -0500 |
|---|---|---|
| committer | Ranjani Vaidyanathan <ra5478@freescale.com> | 2012-11-05 12:14:04 -0600 |
| commit | 24a51586c5a00ddf8b5e5de749f8269951f2de3f (patch) | |
| tree | df4767388f28717099b3df69d2d4c9394eb34ed8 /arch | |
| parent | e21b0b06f4b99a22f9cf5d63641c00a6d83d433a (diff) | |
ENGR00232326 MX6x-Fix incorrect I2C bitrate
IPG_PERCLK is the parent of I2C. I2C needs a minimum of
12.8MHz as its input clock to achieve 400KHz speed. Hence
change the IPG_PERCLK speed accordingly.
MX6DQ/MX6DL - Set IPG_PERCLK at 22MHz (sourced from IPG_CLK)
MX6SL - Set IPG_PERCLK to 24MHz(Sourced from 24MHz XTAL).
Signed-off-by: Ranjani Vaidyanathan <ra5478@freescale.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/mach-mx6/clock.c | 11 | ||||
| -rwxr-xr-x | arch/arm/mach-mx6/clock_mx6sl.c | 11 |
2 files changed, 15 insertions, 7 deletions
diff --git a/arch/arm/mach-mx6/clock.c b/arch/arm/mach-mx6/clock.c index bbddb94cd774..fb4055c80e82 100644 --- a/arch/arm/mach-mx6/clock.c +++ b/arch/arm/mach-mx6/clock.c @@ -4244,7 +4244,7 @@ static struct clk caam_clk[] = { __INIT_CLK_DEBUG(caam_ipg_clk) .id = 2, .enable_reg = MXC_CCM_CCGR0, - .enable_shift = MXC_CCM_CCGRx_CG6_OFFSET, + .enable_shift = MXC_CCM_CCGRx_CG4_OFFSET, .enable = _clk_enable, .disable = _clk_disable, .parent = &mmdc_ch0_axi_clk[0], @@ -5343,8 +5343,13 @@ int __init mx6_clocks_init(unsigned long ckil, unsigned long osc, clk_debug_register(lookups[i].clk); } - /* Lower the ipg_perclk frequency to 6MHz. */ - clk_set_rate(&ipg_perclk, 6000000); + /* Lower the ipg_perclk frequency to 22MHz. + * I2C needs a minimum of 12.8MHz as its source + * to acheive 400KHz speed. IPG_PERCLK sources + * I2C. 22MHz when divided by the I2C divider gives the + * freq closest to 400KHz. + */ + clk_set_rate(&ipg_perclk, 22000000); /* Timer needs to be initialized first as the * the WAIT routines use GPT counter as diff --git a/arch/arm/mach-mx6/clock_mx6sl.c b/arch/arm/mach-mx6/clock_mx6sl.c index 544b9951baef..961e7ee829ff 100755 --- a/arch/arm/mach-mx6/clock_mx6sl.c +++ b/arch/arm/mach-mx6/clock_mx6sl.c @@ -4003,11 +4003,14 @@ int __init mx6sl_clocks_init(unsigned long ckil, unsigned long osc, * should be from OSC24M */ clk_set_parent(&ipg_perclk, &osc_clk); - /* Need to set IPG_PERCLK to 3MHz, so that we can - * satisfy the 2.5:1 AHB:IPG_PERCLK ratio. Since AHB - * can be dropped to as low as 8MHz in low power mode. + + /*IPG_PERCLK sources I2C. + * I2C needs a minimum of 12.8MHz as its source + * to acheive 400KHz speed. + * Hence set ipg_perclk to 24MHz. */ - clk_set_rate(&ipg_perclk, 3000000); + + clk_set_rate(&ipg_perclk, 24000000); gpt_clk[0].parent = &ipg_perclk; gpt_clk[0].get_rate = NULL; |