6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Richard Fitzgerald rf@opensource.cirrus.com
[ Upstream commit 769c1b79295c38d60fde4c0a8f5f31e01360c54f ]
When SPI is used for control, the driver must hold the SPI bus lock while issuing the sequence of writes to perform a soft reset.
From the time the driver writes the SYSTEM_RESET command until the
driver does a write to terminate the reset, there must not be any activity on the SPI bus lines. If there is any SPI activity during the soft-reset, another soft-reset will be triggered. The state of the SPI chip select is irrelevant.
A repeated soft-reset does not in itself cause any problems, and it is not an infinite loop. The problem is a race between these resets and the driver polling for boot completion. There is a time window between soft resets where the driver could read HALO_STATE as 2 (fully booted) while the chip is actually soft-resetting. Although this window is small, it is long enough that it is possible to hit it in normal operation.
To prevent this race and ensure the chip really is fully booted, the driver calls spi_bus_lock() to prevent other activity while resetting. It then issues the SYSTEM_RESET mailbox command. After allowing sufficient time for reset to take effect, the driver issues a PING mailbox command, which will force completion of the full soft-reset sequence. The SPI bus lock can then be released. The mailbox is checked for any boot or wakeup response from the firmware, before the value in HALO_STATE will be trusted.
This does not affect SoundWire or I2C control.
Fixes: 8a731fd37f8b ("ASoC: cs35l56: Move utility functions to shared file") Signed-off-by: Richard Fitzgerald rf@opensource.cirrus.com Link: https://patch.msgid.link/20250225131843.113752-3-rf@opensource.cirrus.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/sound/cs35l56.h | 31 ++++++++++++ sound/pci/hda/cs35l56_hda_spi.c | 3 ++ sound/soc/codecs/cs35l56-shared.c | 80 +++++++++++++++++++++++++++++++ sound/soc/codecs/cs35l56-spi.c | 3 ++ 4 files changed, 117 insertions(+)
diff --git a/include/sound/cs35l56.h b/include/sound/cs35l56.h index 3dc7a1551ac35..5d653a3491d07 100644 --- a/include/sound/cs35l56.h +++ b/include/sound/cs35l56.h @@ -12,6 +12,7 @@ #include <linux/firmware/cirrus/cs_dsp.h> #include <linux/regulator/consumer.h> #include <linux/regmap.h> +#include <linux/spi/spi.h> #include <sound/cs-amp-lib.h>
#define CS35L56_DEVID 0x0000000 @@ -61,6 +62,7 @@ #define CS35L56_IRQ1_MASK_8 0x000E0AC #define CS35L56_IRQ1_MASK_18 0x000E0D4 #define CS35L56_IRQ1_MASK_20 0x000E0DC +#define CS35L56_DSP_MBOX_1_RAW 0x0011000 #define CS35L56_DSP_VIRTUAL1_MBOX_1 0x0011020 #define CS35L56_DSP_VIRTUAL1_MBOX_2 0x0011024 #define CS35L56_DSP_VIRTUAL1_MBOX_3 0x0011028 @@ -224,6 +226,7 @@ #define CS35L56_HALO_STATE_SHUTDOWN 1 #define CS35L56_HALO_STATE_BOOT_DONE 2
+#define CS35L56_MBOX_CMD_PING 0x0A000000 #define CS35L56_MBOX_CMD_AUDIO_PLAY 0x0B000001 #define CS35L56_MBOX_CMD_AUDIO_PAUSE 0x0B000002 #define CS35L56_MBOX_CMD_AUDIO_REINIT 0x0B000003 @@ -254,6 +257,16 @@ #define CS35L56_NUM_BULK_SUPPLIES 3 #define CS35L56_NUM_DSP_REGIONS 5
+/* Additional margin for SYSTEM_RESET to control port ready on SPI */ +#define CS35L56_SPI_RESET_TO_PORT_READY_US (CS35L56_CONTROL_PORT_READY_US + 2500) + +struct cs35l56_spi_payload { + __be32 addr; + __be16 pad; + __be32 value; +} __packed; +static_assert(sizeof(struct cs35l56_spi_payload) == 10); + struct cs35l56_base { struct device *dev; struct regmap *regmap; @@ -269,6 +282,7 @@ struct cs35l56_base { s8 cal_index; struct cirrus_amp_cal_data cal_data; struct gpio_desc *reset_gpio; + struct cs35l56_spi_payload *spi_payload_buf; };
static inline bool cs35l56_is_otp_register(unsigned int reg) @@ -276,6 +290,23 @@ static inline bool cs35l56_is_otp_register(unsigned int reg) return (reg >> 16) == 3; }
+static inline int cs35l56_init_config_for_spi(struct cs35l56_base *cs35l56, + struct spi_device *spi) +{ + cs35l56->spi_payload_buf = devm_kzalloc(&spi->dev, + sizeof(*cs35l56->spi_payload_buf), + GFP_KERNEL | GFP_DMA); + if (!cs35l56->spi_payload_buf) + return -ENOMEM; + + return 0; +} + +static inline bool cs35l56_is_spi(struct cs35l56_base *cs35l56) +{ + return IS_ENABLED(CONFIG_SPI_MASTER) && !!cs35l56->spi_payload_buf; +} + extern const struct regmap_config cs35l56_regmap_i2c; extern const struct regmap_config cs35l56_regmap_spi; extern const struct regmap_config cs35l56_regmap_sdw; diff --git a/sound/pci/hda/cs35l56_hda_spi.c b/sound/pci/hda/cs35l56_hda_spi.c index 7f02155fe61e3..7c94110b6272a 100644 --- a/sound/pci/hda/cs35l56_hda_spi.c +++ b/sound/pci/hda/cs35l56_hda_spi.c @@ -22,6 +22,9 @@ static int cs35l56_hda_spi_probe(struct spi_device *spi) return -ENOMEM;
cs35l56->base.dev = &spi->dev; + ret = cs35l56_init_config_for_spi(&cs35l56->base, spi); + if (ret) + return ret;
#ifdef CS35L56_WAKE_HOLD_TIME_US cs35l56->base.can_hibernate = true; diff --git a/sound/soc/codecs/cs35l56-shared.c b/sound/soc/codecs/cs35l56-shared.c index e45e9ae01bc66..195841a567c3d 100644 --- a/sound/soc/codecs/cs35l56-shared.c +++ b/sound/soc/codecs/cs35l56-shared.c @@ -10,6 +10,7 @@ #include <linux/gpio/consumer.h> #include <linux/regmap.h> #include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> #include <linux/types.h> #include <sound/cs-amp-lib.h>
@@ -303,6 +304,79 @@ void cs35l56_wait_min_reset_pulse(void) } EXPORT_SYMBOL_NS_GPL(cs35l56_wait_min_reset_pulse, SND_SOC_CS35L56_SHARED);
+static const struct { + u32 addr; + u32 value; +} cs35l56_spi_system_reset_stages[] = { + { .addr = CS35L56_DSP_VIRTUAL1_MBOX_1, .value = CS35L56_MBOX_CMD_SYSTEM_RESET }, + /* The next write is necessary to delimit the soft reset */ + { .addr = CS35L56_DSP_MBOX_1_RAW, .value = CS35L56_MBOX_CMD_PING }, +}; + +static void cs35l56_spi_issue_bus_locked_reset(struct cs35l56_base *cs35l56_base, + struct spi_device *spi) +{ + struct cs35l56_spi_payload *buf = cs35l56_base->spi_payload_buf; + struct spi_transfer t = { + .tx_buf = buf, + .len = sizeof(*buf), + }; + struct spi_message m; + int i, ret; + + for (i = 0; i < ARRAY_SIZE(cs35l56_spi_system_reset_stages); i++) { + buf->addr = cpu_to_be32(cs35l56_spi_system_reset_stages[i].addr); + buf->value = cpu_to_be32(cs35l56_spi_system_reset_stages[i].value); + spi_message_init_with_transfers(&m, &t, 1); + ret = spi_sync_locked(spi, &m); + if (ret) + dev_warn(cs35l56_base->dev, "spi_sync failed: %d\n", ret); + + usleep_range(CS35L56_SPI_RESET_TO_PORT_READY_US, + 2 * CS35L56_SPI_RESET_TO_PORT_READY_US); + } +} + +static void cs35l56_spi_system_reset(struct cs35l56_base *cs35l56_base) +{ + struct spi_device *spi = to_spi_device(cs35l56_base->dev); + unsigned int val; + int read_ret, ret; + + /* + * There must not be any other SPI bus activity while the amp is + * soft-resetting. + */ + ret = spi_bus_lock(spi->controller); + if (ret) { + dev_warn(cs35l56_base->dev, "spi_bus_lock failed: %d\n", ret); + return; + } + + cs35l56_spi_issue_bus_locked_reset(cs35l56_base, spi); + spi_bus_unlock(spi->controller); + + /* + * Check firmware boot by testing for a response in MBOX_2. + * HALO_STATE cannot be trusted yet because the reset sequence + * can leave it with stale state. But MBOX is reset. + * The regmap must remain in cache-only until the chip has + * booted, so use a bypassed read. + */ + ret = read_poll_timeout(regmap_read_bypassed, read_ret, + (val > 0) && (val < 0xffffffff), + CS35L56_HALO_STATE_POLL_US, + CS35L56_HALO_STATE_TIMEOUT_US, + false, + cs35l56_base->regmap, + CS35L56_DSP_VIRTUAL1_MBOX_2, + &val); + if (ret) { + dev_err(cs35l56_base->dev, "SPI reboot timed out(%d): MBOX2=%#x\n", + read_ret, val); + } +} + static const struct reg_sequence cs35l56_system_reset_seq[] = { REG_SEQ0(CS35L56_DSP1_HALO_STATE, 0), REG_SEQ0(CS35L56_DSP_VIRTUAL1_MBOX_1, CS35L56_MBOX_CMD_SYSTEM_RESET), @@ -315,6 +389,12 @@ void cs35l56_system_reset(struct cs35l56_base *cs35l56_base, bool is_soundwire) * accesses other than the controlled system reset sequence below. */ regcache_cache_only(cs35l56_base->regmap, true); + + if (cs35l56_is_spi(cs35l56_base)) { + cs35l56_spi_system_reset(cs35l56_base); + return; + } + regmap_multi_reg_write_bypassed(cs35l56_base->regmap, cs35l56_system_reset_seq, ARRAY_SIZE(cs35l56_system_reset_seq)); diff --git a/sound/soc/codecs/cs35l56-spi.c b/sound/soc/codecs/cs35l56-spi.c index b07b798b0b45d..568f554a8638b 100644 --- a/sound/soc/codecs/cs35l56-spi.c +++ b/sound/soc/codecs/cs35l56-spi.c @@ -33,6 +33,9 @@ static int cs35l56_spi_probe(struct spi_device *spi)
cs35l56->base.dev = &spi->dev; cs35l56->base.can_hibernate = true; + ret = cs35l56_init_config_for_spi(&cs35l56->base, spi); + if (ret) + return ret;
ret = cs35l56_common_probe(cs35l56); if (ret != 0)