Implement suspend/resume capabilities (not runtime_pm for now)
Credits: this patch is based on an earlier internal contribution by Vinod Koul, Sanyog Kale, Shreyas Nc and Hardik Shah.
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com --- drivers/soundwire/cadence_master.c | 18 ++-- drivers/soundwire/cadence_master.h | 2 +- drivers/soundwire/intel.c | 128 ++++++++++++++++++++++++++++- 3 files changed, 140 insertions(+), 8 deletions(-)
diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index bd58d80ff636..fdf9eec7cde1 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -823,14 +823,17 @@ EXPORT_SYMBOL(sdw_cdns_exit_reset); * sdw_cdns_enable_interrupt() - Enable SDW interrupts and update config * @cdns: Cadence instance */ -int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns) +int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns, bool state) { - u32 mask; + u32 slave_intmask0 = 0; + u32 slave_intmask1 = 0; + u32 mask = 0; + + if (!state) + goto update_masks;
- cdns_writel(cdns, CDNS_MCP_SLAVE_INTMASK0, - CDNS_MCP_SLAVE_INTMASK0_MASK); - cdns_writel(cdns, CDNS_MCP_SLAVE_INTMASK1, - CDNS_MCP_SLAVE_INTMASK1_MASK); + slave_intmask0 = CDNS_MCP_SLAVE_INTMASK0_MASK; + slave_intmask1 = CDNS_MCP_SLAVE_INTMASK1_MASK;
/* enable detection of all slave state changes */ mask = CDNS_MCP_INT_SLAVE_MASK; @@ -853,6 +856,9 @@ int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns) if (interrupt_mask) /* parameter override */ mask = interrupt_mask;
+update_masks: + cdns_writel(cdns, CDNS_MCP_SLAVE_INTMASK0, slave_intmask0); + cdns_writel(cdns, CDNS_MCP_SLAVE_INTMASK1, slave_intmask1); cdns_writel(cdns, CDNS_MCP_INTMASK, mask);
/* commit changes */ diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index 1a67728c5000..302351808098 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -162,7 +162,7 @@ int sdw_cdns_init(struct sdw_cdns *cdns); int sdw_cdns_pdi_init(struct sdw_cdns *cdns, struct sdw_cdns_stream_config config); int sdw_cdns_exit_reset(struct sdw_cdns *cdns); -int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns); +int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns, bool state);
#ifdef CONFIG_DEBUG_FS void sdw_cdns_debugfs_init(struct sdw_cdns *cdns, struct dentry *root); diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 3d22c9023a9b..42bdc870c3ee 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -12,6 +12,7 @@ #include <linux/interrupt.h> #include <linux/platform_device.h> #include <sound/pcm_params.h> +#include <linux/pm_runtime.h> #include <sound/soc.h> #include <linux/soundwire/sdw_registers.h> #include <linux/soundwire/sdw.h> @@ -284,6 +285,35 @@ static void intel_debugfs_exit(struct sdw_intel *sdw) {} /* * shim ops */ +static int intel_link_power_down(struct sdw_intel *sdw) +{ + int link_control, spa_mask, cpa_mask, ret; + unsigned int link_id = sdw->instance; + void __iomem *shim = sdw->res->shim; + u16 ioctl; + + /* Glue logic */ + ioctl = intel_readw(shim, SDW_SHIM_IOCTL(link_id)); + ioctl |= SDW_SHIM_IOCTL_BKE; + ioctl |= SDW_SHIM_IOCTL_COE; + intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl); + + ioctl &= ~(SDW_SHIM_IOCTL_MIF); + intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl); + + /* Link power down sequence */ + link_control = intel_readl(shim, SDW_SHIM_LCTL); + spa_mask = ~(SDW_SHIM_LCTL_SPA << link_id); + cpa_mask = (SDW_SHIM_LCTL_CPA << link_id); + link_control &= spa_mask; + + ret = intel_clear_bit(shim, SDW_SHIM_LCTL, link_control, cpa_mask); + if (ret < 0) + return ret; + + sdw->cdns.link_up = false; + return 0; +}
static int intel_link_power_up(struct sdw_intel *sdw) { @@ -306,6 +336,29 @@ static int intel_link_power_up(struct sdw_intel *sdw) return 0; }
+static void intel_shim_wake(struct sdw_intel *sdw, bool wake_enable) +{ + void __iomem *shim = sdw->res->shim; + unsigned int link_id = sdw->instance; + u16 wake_en, wake_sts; + + if (wake_enable) { + /* Enable the wakeup */ + intel_writew(shim, SDW_SHIM_WAKEEN, + (SDW_SHIM_WAKEEN_ENABLE << link_id)); + } else { + /* Disable the wake up interrupt */ + wake_en = intel_readw(shim, SDW_SHIM_WAKEEN); + wake_en &= ~(SDW_SHIM_WAKEEN_ENABLE << link_id); + intel_writew(shim, SDW_SHIM_WAKEEN, wake_en); + + /* Clear wake status */ + wake_sts = intel_readw(shim, SDW_SHIM_WAKESTS); + wake_sts |= (SDW_SHIM_WAKEEN_ENABLE << link_id); + intel_writew(shim, SDW_SHIM_WAKESTS_STATUS, wake_sts); + } +} + static int intel_shim_init(struct sdw_intel *sdw) { void __iomem *shim = sdw->res->shim; @@ -1066,7 +1119,7 @@ static int intel_probe(struct platform_device *pdev) goto err_init; }
- ret = sdw_cdns_enable_interrupt(&sdw->cdns); + ret = sdw_cdns_enable_interrupt(&sdw->cdns, true); if (ret < 0) { dev_err(sdw->cdns.dev, "cannot enable interrupts\n"); goto err_init; @@ -1114,11 +1167,84 @@ static int intel_remove(struct platform_device *pdev) return 0; }
+/* + * PM calls + */ + +#ifdef CONFIG_PM + +static int intel_suspend(struct device *dev) +{ + struct sdw_intel *sdw = dev_get_drvdata(dev); + int ret; + + if (sdw->cdns.bus.prop.hw_disabled) { + dev_dbg(dev, "SoundWire master %d is disabled, ignoring\n", + sdw->cdns.bus.link_id); + return 0; + } + + ret = sdw_cdns_enable_interrupt(&sdw->cdns, false); + if (ret < 0) { + dev_err(sdw->cdns.dev, "cannot disable interrupts on suspend\n"); + return ret; + } + + ret = intel_link_power_down(sdw); + if (ret) { + dev_err(dev, "Link power down failed: %d", ret); + return ret; + } + + intel_shim_wake(sdw, false); + + return 0; +} + +static int intel_resume(struct device *dev) +{ + struct sdw_intel *sdw = dev_get_drvdata(dev); + int ret; + + if (sdw->cdns.bus.prop.hw_disabled) { + dev_dbg(dev, "SoundWire master %d is disabled, ignoring\n", + sdw->cdns.bus.link_id); + return 0; + } + + ret = intel_init(sdw); + if (ret) { + dev_err(dev, "%s failed: %d", __func__, ret); + return ret; + } + + ret = sdw_cdns_enable_interrupt(&sdw->cdns, true); + if (ret < 0) { + dev_err(sdw->cdns.dev, "cannot enable interrupts during resume\n"); + return ret; + } + + ret = sdw_cdns_exit_reset(&sdw->cdns); + if (ret < 0) { + dev_err(sdw->cdns.dev, "unable to exit bus reset sequence during resume\n"); + return ret; + } + + return ret; +} + +#endif + +static const struct dev_pm_ops intel_pm = { + SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume) +}; + static struct platform_driver sdw_intel_drv = { .probe = intel_probe, .remove = intel_remove, .driver = { .name = "int-sdw", + .pm = &intel_pm,
}, };