On 13 March 2018 at 06:10, Harish Jenny K N <harish_kandiga@xxxxxxxxxx> wrote: > This patch exports the host capabilities to debugfs > > This idea of sharing host capabilities over debugfs > came up from Abbas Raza <Abbas_Raza@xxxxxxxxxx> > Earlier discussions: > https://lkml.org/lkml/2018/3/5/357 > https://www.spinics.net/lists/linux-mmc/msg48219.html > > Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> > Signed-off-by: Harish Jenny K N <harish_kandiga@xxxxxxxxxx> > --- > > Changes in v10: > - minor review comment addressed. > - Added "Reviewed-by" line > > Changes in v9 > - More code cleanup as suggested by Andy Shevchenko. > > Changes in v8 > - Changes to use for_each_set_bit as suggested by Andy Shevchenko. > > Changes in v7 > - Moved additional capabilities also to caps file as mentioned by Ulf Hansson > - compacting the code with macros > > Changes in v6: > - Used DEFINE_SHOW_ATTRIBUTE > > Changes in v5: > - Added parser logic in kernel by using debugfs_create_file for caps and caps2 instead of debugfs_create_x32 > - Changed Author > > Changes in v4: > - Moved the creation of nodes to mmc_add_host_debugfs > - Exported caps2 > - Renamed host_caps to caps > > Changes in v3: > - Removed typecasting of &host->caps to (u32 *) > > Changes in v2: > - Changed Author > > drivers/mmc/core/debugfs.c | 107 +++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 107 insertions(+) > > diff --git a/drivers/mmc/core/debugfs.c b/drivers/mmc/core/debugfs.c > index c51e0c0..826d361 100644 > --- a/drivers/mmc/core/debugfs.c > +++ b/drivers/mmc/core/debugfs.c > @@ -225,6 +225,110 @@ static int mmc_clock_opt_set(void *data, u64 val) > DEFINE_SIMPLE_ATTRIBUTE(mmc_clock_fops, mmc_clock_opt_get, mmc_clock_opt_set, > "%llu\n"); > > +/* > + * mmc_host_capabilities - MMC host capabilities > + * > + * This must be in sync with caps definitions in the mmc/host.h > + */ > +static const char * const mmc_host_capabilities[] = { > + "4-bit transfers allowed", > + "Supports MMC high-speed timing", > + "Supports SD high-speed timing", > + "Can signal pending SDIO IRQs", > + "Talks only SPI protocols", > + "Needs polling for card-detection", > + "8 bit transfers allowed", > + "Suspends (e)MMC/SD at idle", > + "Nonremovable", > + "Waits while card is busy", > + "Allows erase/trim commands", > + "Supports DDR mode at 3.3V", > + "Supports DDR mode at 1.8V", > + "Supports DDR mode at 1.2V", > + "Can power off after boot", > + "CMD14/CMD19 bus width ok", > + "Supports UHS SDR12 mode", > + "Supports UHS SDR25 mode", > + "Supports UHS SDR50 mode", > + "Supports UHS SDR104 mode", > + "Supports UHS DDR50 mode", > + "Unknown (bit 21)", > + "Unknown (bit 22)", > + "Supports Driver Type A", > + "Supports Driver Type C", > + "Supports Driver Type D", > + "Unknown (bit 26)", > + "RW reqs can be completed within mmc_request_done()", > + "Supports Enable card detect wake", > + "Can send commands during data transfer", > + "CMD23 supported", > + "Supports Hardware reset" > +}; > + > +/* > + * mmc_host_capabilities2 - MMC host additional capabilities > + * > + * This must be in sync with caps2 definitions in the mmc/host.h > + */ > +static const char * const mmc_host_capabilities2[] = { > + "No access to Boot partition", > + "Unknown (bit 1)", > + "Can do full power cycle", > + "Unknown (bit 3)", > + "Unknown (bit 4)", > + "Supports HS200 1.8V SDR", > + "Supports HS200 1.2V SDR", > + "Unknown (bit 7)", > + "Unknown (bit 8)", > + "Unknown (bit 9)", > + "Card-detect signal active high", > + "Write-protect signal active high", > + "Unknown (bit 12)", > + "Unknown (bit 13)", > + "Can do complete power cycle of the card", > + "Supports HS400 1.8V", > + "Support HS400 1.2V", > + "SDIO IRQ - Nothread", > + "No physical write protect pin, assume always read-write", > + "Do not send SDIO commands during initialization", > + "Supports enhanced strobe", > + "Do not send SD commands during initialization", > + "Do not send (e)MMC commands during initialization", > + "Has eMMC command queue engine", > + "CQE can issue a direct command", > + "Unknown (bit 25)", > + "Unknown (bit 26)", > + "Unknown (bit 27)", > + "Unknown (bit 28)", > + "Unknown (bit 29)", > + "Unknown (bit 30)", > + "Unknown (bit 31)" > +}; Honestly, I don't like this, but maybe other people do, then I am fine with this approach. If were to decide, I would just rather print the caps field in a hexadecimal bit form and leave the translation to the user. > + > +static int mmc_caps_show(struct seq_file *s, void *unused) > +{ > + struct mmc_host *host = s->private; > + unsigned long caps = host->caps; > + unsigned long caps2 = host->caps2; > + int bit; > + > + seq_puts(s, "MMC Host capabilities are:\n"); > + seq_puts(s, "=============================================\n"); > + > + for_each_set_bit(bit, &caps, ARRAY_SIZE(mmc_host_capabilities)) > + seq_printf(s, "%s\n", mmc_host_capabilities[bit]); > + > + seq_puts(s, "=============================================\n"); > + seq_puts(s, "MMC Host additional capabilities are:\n"); > + seq_puts(s, "=============================================\n"); > + > + for_each_set_bit(bit, &caps2, ARRAY_SIZE(mmc_host_capabilities2)) > + seq_printf(s, "%s\n", mmc_host_capabilities2[bit]); > + > + return 0; > +} > +DEFINE_SHOW_ATTRIBUTE(mmc_caps); > + > void mmc_add_host_debugfs(struct mmc_host *host) > { > struct dentry *root; > @@ -243,6 +347,9 @@ void mmc_add_host_debugfs(struct mmc_host *host) > if (!debugfs_create_file("ios", S_IRUSR, root, host, &mmc_ios_fops)) > goto err_node; > > + if (!debugfs_create_file("caps", 0400, root, host, &mmc_caps_fops)) > + goto err_node; > + > if (!debugfs_create_file("clock", S_IRUSR | S_IWUSR, root, host, > &mmc_clock_fops)) > goto err_node; > -- > 1.9.1 > Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
