On 03/21/2012 04:41 PM, ludovic.desroches@xxxxxxxxx :
> From: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
>
> 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.desroches@xxxxxxxxx>
Otherwise:
Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
> ---
> 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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