From d2234596be2192d9c1ae34f8c7534531191bc433 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 19 Aug 2024 08:55:47 +0800 Subject: [PATCH] soundwire: intel: add probe-time check on link id MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In older platforms, the number of links was constant and hard-coded to 4. Newer platforms can have varying number of links, so we need to add a probe-time check to make sure the ACPI-reported information with _DSD properties is aligned with hardware capabilities reported in the SoundWire LCAP register. Acked-by: Vinod Koul Signed-off-by: Pierre-Louis Bossart Reviewed-by: Péter Ujfalusi Signed-off-by: Bard Liao Acked-by: Mark Brown Reviewed-by: Takashi Iwai Link: https://patch.msgid.link/20240819005548.5867-3-yung-chuan.liao@linux.intel.com Signed-off-by: Mark Brown --- drivers/soundwire/intel.h | 7 +++++++ drivers/soundwire/intel_ace2x.c | 20 ++++++++++++++++++++ drivers/soundwire/intel_auxdevice.c | 14 ++++++++++++++ include/linux/soundwire/sdw_intel.h | 3 +++ 4 files changed, 44 insertions(+) diff --git a/drivers/soundwire/intel.h b/drivers/soundwire/intel.h index 68838e843b543e..1db4d9d3a3ba64 100644 --- a/drivers/soundwire/intel.h +++ b/drivers/soundwire/intel.h @@ -222,6 +222,13 @@ static inline bool sdw_intel_sync_check_cmdsync_unlocked(struct sdw_intel *sdw) return false; } +static inline int sdw_intel_get_link_count(struct sdw_intel *sdw) +{ + if (SDW_INTEL_CHECK_OPS(sdw, get_link_count)) + return SDW_INTEL_OPS(sdw, get_link_count)(sdw); + return 4; /* default on older generations */ +} + /* common bus management */ int intel_start_bus(struct sdw_intel *sdw); int intel_start_bus_after_reset(struct sdw_intel *sdw); diff --git a/drivers/soundwire/intel_ace2x.c b/drivers/soundwire/intel_ace2x.c index 781fe0aefa68ff..fff312c6968dd3 100644 --- a/drivers/soundwire/intel_ace2x.c +++ b/drivers/soundwire/intel_ace2x.c @@ -706,10 +706,30 @@ static void intel_program_sdi(struct sdw_intel *sdw, int dev_num) __func__, sdw->instance, dev_num); } +static int intel_get_link_count(struct sdw_intel *sdw) +{ + int ret; + + ret = hdac_bus_eml_get_count(sdw->link_res->hbus, true, AZX_REG_ML_LEPTR_ID_SDW); + if (!ret) { + dev_err(sdw->cdns.dev, "%s: could not retrieve link count\n", __func__); + return -ENODEV; + } + + if (ret > SDW_INTEL_MAX_LINKS) { + dev_err(sdw->cdns.dev, "%s: link count %d exceed max %d\n", __func__, ret, SDW_INTEL_MAX_LINKS); + return -EINVAL; + } + + return ret; +} + const struct sdw_intel_hw_ops sdw_intel_lnl_hw_ops = { .debugfs_init = intel_ace2x_debugfs_init, .debugfs_exit = intel_ace2x_debugfs_exit, + .get_link_count = intel_get_link_count, + .register_dai = intel_register_dai, .check_clock_stop = intel_check_clock_stop, diff --git a/drivers/soundwire/intel_auxdevice.c b/drivers/soundwire/intel_auxdevice.c index 8807e01cbf7c7e..d110f2b587d5e2 100644 --- a/drivers/soundwire/intel_auxdevice.c +++ b/drivers/soundwire/intel_auxdevice.c @@ -317,6 +317,20 @@ static int intel_link_probe(struct auxiliary_device *auxdev, bus->link_id = auxdev->id; bus->clk_stop_timeout = 1; + /* + * paranoia check: make sure ACPI-reported number of links is aligned with + * hardware capabilities. + */ + ret = sdw_intel_get_link_count(sdw); + if (ret < 0) { + dev_err(dev, "%s: sdw_intel_get_link_count failed: %d\n", __func__, ret); + return ret; + } + if (ret <= sdw->instance) { + dev_err(dev, "%s: invalid link id %d, link count %d\n", __func__, auxdev->id, ret); + return -EINVAL; + } + sdw_cdns_probe(cdns); /* Set ops */ diff --git a/include/linux/soundwire/sdw_intel.h b/include/linux/soundwire/sdw_intel.h index 87d82ea9a13a76..cb8e7396b4db1d 100644 --- a/include/linux/soundwire/sdw_intel.h +++ b/include/linux/soundwire/sdw_intel.h @@ -388,6 +388,7 @@ struct sdw_intel; /* struct intel_sdw_hw_ops - SoundWire ops for Intel platforms. * @debugfs_init: initialize all debugfs capabilities * @debugfs_exit: close and cleanup debugfs capabilities + * @get_link_count: fetch link count from hardware registers * @register_dai: read all PDI information and register DAIs * @check_clock_stop: throw error message if clock is not stopped. * @start_bus: normal start @@ -412,6 +413,8 @@ struct sdw_intel_hw_ops { void (*debugfs_init)(struct sdw_intel *sdw); void (*debugfs_exit)(struct sdw_intel *sdw); + int (*get_link_count)(struct sdw_intel *sdw); + int (*register_dai)(struct sdw_intel *sdw); void (*check_clock_stop)(struct sdw_intel *sdw);