Hi, This looks like the best of the min_freq patches I've seen, and is implementing a suggestion of Pierre's. Should we take it?
- Chris. On Tue, Jan 05, 2010 at 05:58:34AM +0800, Hein_Tibosch wrote: > > In my last mail the spaces in the patch were mistreated, sorry for that. > > Below a patch which tries mmc-initialization using several frequencies > from an array 400, 300, 200 and 100. > > > Signed-off-by: Hein Tibosch <[email protected]> > > --- > diff -Nurp a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -891,12 +891,7 @@ static void mmc_power_up(struct mmc_host > */ > mmc_delay(10); > > - if (host->f_min > 400000) { > - pr_warning("%s: Minimum clock frequency too high for " > - "identification mode\n", mmc_hostname(host)); > - host->ios.clock = host->f_min; > - } else > - host->ios.clock = 400000; > + host->ios.clock = host->f_init; > > host->ios.power_mode = MMC_POWER_ON; > mmc_set_ios(host); > @@ -1041,6 +1036,8 @@ void mmc_rescan(struct work_struct *work > container_of(work, struct mmc_host, detect.work); > u32 ocr; > int err; > + int i; > + unsigned freqs[] = { 400000, 300000, 200000, 100000 }; > > mmc_bus_get(host); > > @@ -1070,46 +1067,55 @@ void mmc_rescan(struct work_struct *work > if (host->ops->get_cd && host->ops->get_cd(host) == 0) > goto out; > > - mmc_claim_host(host); > + for (i = 0; i < ARRAY_SIZE(freqs); i++) { > + mmc_claim_host(host); > > - mmc_power_up(host); > - mmc_go_idle(host); > + if (freqs[i] >= host->f_min) > + host->f_init = freqs[i]; > + else if (i && freqs[i-1] <= host->f_min) > + goto out; > + else > + host->f_init = host->f_min; > > - mmc_send_if_cond(host, host->ocr_avail); > + printk ("mmc_rescan: trying %u Hz\n", host->f_init); > + mmc_power_up(host); > + mmc_go_idle(host); > > - /* > - * First we search for SDIO... > - */ > - err = mmc_send_io_op_cond(host, 0, &ocr); > - if (!err) { > - if (mmc_attach_sdio(host, ocr)) > - mmc_power_off(host); > - goto out; > - } > + mmc_send_if_cond(host, host->ocr_avail); > > - /* > - * ...then normal SD... > - */ > - err = mmc_send_app_op_cond(host, 0, &ocr); > - if (!err) { > - if (mmc_attach_sd(host, ocr)) > - mmc_power_off(host); > - goto out; > - } > + /* > + * First we search for SDIO... > + */ > + err = mmc_send_io_op_cond(host, 0, &ocr); > + if (!err) { > + if (mmc_attach_sdio(host, ocr)) > + mmc_power_off(host); > + goto out; > + } > > - /* > - * ...and finally MMC. > - */ > - err = mmc_send_op_cond(host, 0, &ocr); > - if (!err) { > - if (mmc_attach_mmc(host, ocr)) > - mmc_power_off(host); > - goto out; > - } > + /* > + * ...then normal SD... > + */ > + err = mmc_send_app_op_cond(host, 0, &ocr); > + if (!err) { > + if (mmc_attach_sd(host, ocr)) > + mmc_power_off(host); > + goto out; > + } > > - mmc_release_host(host); > - mmc_power_off(host); > + /* > + * ...and finally MMC. > + */ > + err = mmc_send_op_cond(host, 0, &ocr); > + if (!err) { > + if (mmc_attach_mmc(host, ocr)) > + mmc_power_off(host); > + goto out; > + } > > + mmc_release_host(host); > + mmc_power_off(host); > + } > out: > if (host->caps & MMC_CAP_NEEDS_POLL) > mmc_schedule_delayed_work(&host->detect, HZ); > diff -Nurp a/include/linux/mmc/host.h b/include/linux/mmc/host.h > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -119,6 +119,7 @@ struct mmc_host { > const struct mmc_host_ops *ops; > unsigned int f_min; > unsigned int f_max; > + unsigned int f_init; > u32 ocr_avail; > > #define MMC_VDD_165_195 0x00000080 /* VDD voltage 1.65 - > 1.95 */ > > > -- -- Chris Ball <[email protected]> <http://printf.net/> One Laptop Per Child -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
