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)" +}; + +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 -- 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
