On 03/21/2012 04:41 PM, ludovic.desroc...@atmel.com :
> From: Ludovic Desroches <ludovic.desroc...@atmel.com>
> 
> Add an odd clock divider capability available from v5xx. It also involves
> changing the clock divider calculation.

Also tell here that you have changed the way that the switch/case
directive has been implemented.

> Signed-off-by: Ludovic Desroches <ludovic.desroc...@atmel.com>

Otherwise:
Acked-by: Nicolas Ferre <nicolas.fe...@atmel.com>


> ---
>  drivers/mmc/host/atmel-mci-regs.h |    1 +
>  drivers/mmc/host/atmel-mci.c      |   48 ++++++++++++++++++++++--------------
>  2 files changed, 30 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/mmc/host/atmel-mci-regs.h 
> b/drivers/mmc/host/atmel-mci-regs.h
> index 000b3ad..787aba1 100644
> --- a/drivers/mmc/host/atmel-mci-regs.h
> +++ b/drivers/mmc/host/atmel-mci-regs.h
> @@ -31,6 +31,7 @@
>  # define ATMCI_MR_PDCFBYTE           (  1 << 13)     /* Force Byte Transfer 
> */
>  # define ATMCI_MR_PDCPADV            (  1 << 14)     /* Padding Value */
>  # define ATMCI_MR_PDCMODE            (  1 << 15)     /* PDC-oriented Mode */
> +# define ATMCI_MR_CLKODD(x)          ((x) << 16)     /* LSB of Clock Divider 
> */
>  #define ATMCI_DTOR                   0x0008  /* Data Timeout */
>  # define ATMCI_DTOCYC(x)             ((x) <<  0)     /* Data Timeout Cycles 
> */
>  # define ATMCI_DTOMUL(x)             ((x) <<  4)     /* Data Timeout 
> Multiplier */
> diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
> index 9dcb236..75e28c0 100644
> --- a/drivers/mmc/host/atmel-mci.c
> +++ b/drivers/mmc/host/atmel-mci.c
> @@ -76,6 +76,7 @@ struct atmel_mci_caps {
>       bool    has_cstor_reg;
>       bool    has_highspeed;
>       bool    has_rwproof;
> +     bool    has_odd_clk_div;
>  };
>  
>  struct atmel_mci_dma {
> @@ -1124,16 +1125,27 @@ static void atmci_set_ios(struct mmc_host *mmc, 
> struct mmc_ios *ios)
>               }
>  
>               /* Calculate clock divider */
> -             clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1;
> -             if (clkdiv > 255) {
> -                     dev_warn(&mmc->class_dev,
> -                             "clock %u too slow; using %lu\n",
> -                             clock_min, host->bus_hz / (2 * 256));
> -                     clkdiv = 255;
> +             if (host->caps.has_odd_clk_div) {
> +                     clkdiv = DIV_ROUND_UP(host->bus_hz, clock_min) - 2;
> +                     if (clkdiv > 511) {
> +                             dev_warn(&mmc->class_dev,
> +                                      "clock %u too slow; using %lu\n",
> +                                      clock_min, host->bus_hz / (511 + 2));
> +                             clkdiv = 511;
> +                     }
> +                     host->mode_reg = ATMCI_MR_CLKDIV(clkdiv >> 1)
> +                                      | ATMCI_MR_CLKODD(clkdiv & 1);
> +             } else {
> +                     clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1;
> +                     if (clkdiv > 255) {
> +                             dev_warn(&mmc->class_dev,
> +                                      "clock %u too slow; using %lu\n",
> +                                      clock_min, host->bus_hz / (2 * 256));
> +                             clkdiv = 255;
> +                     }
> +                     host->mode_reg = ATMCI_MR_CLKDIV(clkdiv);
>               }
>  
> -             host->mode_reg = ATMCI_MR_CLKDIV(clkdiv);
> -
>               /*
>                * WRPROOF and RDPROOF prevent overruns/underruns by
>                * stopping the clock when the FIFO is full/empty.
> @@ -2000,37 +2012,35 @@ static void __init atmci_get_cap(struct atmel_mci 
> *host)
>                       "version: 0x%x\n", version);
>  
>       host->caps.has_dma = 0;
> -     host->caps.has_pdc = 0;
> +     host->caps.has_pdc = 1;
>       host->caps.has_cfg_reg = 0;
>       host->caps.has_cstor_reg = 0;
>       host->caps.has_highspeed = 0;
>       host->caps.has_rwproof = 0;
> +     host->caps.has_odd_clk_div = 0;
>  
>       /* keep only major version number */
>       switch (version & 0xf00) {
> -     case 0x100:
> -             host->caps.has_pdc = 1;
> -             break;
> -     case 0x200:
> -             host->caps.has_pdc = 1;
> -             host->caps.has_rwproof = 1;
> -             break;
> -     case 0x300:
> -     case 0x400:
>       case 0x500:
> +             host->caps.has_odd_clk_div = 1;
> +     case 0x400:
> +     case 0x300:
>  #ifdef CONFIG_AT_HDMAC
>               host->caps.has_dma = 1;
>  #else
> -             host->caps.has_dma = 0;
>               dev_info(&host->pdev->dev,
>                       "has dma capability but dma engine is not selected, 
> then use pio\n");
>  #endif
> +             host->caps.has_pdc = 0;
>               host->caps.has_cfg_reg = 1;
>               host->caps.has_cstor_reg = 1;
>               host->caps.has_highspeed = 1;
> +     case 0x200:
>               host->caps.has_rwproof = 1;
> +     case 0x100:
>               break;
>       default:
> +             host->caps.has_pdc = 0;
>               dev_warn(&host->pdev->dev,
>                               "Unmanaged mci version, set minimum 
> capabilities\n");
>               break;


-- 
Nicolas Ferre
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