From 7c5d81620ecd37702e86232de819eb1dd4c738e0 Mon Sep 17 00:00:00 2001 From: Sebastian Reichel Date: Wed, 11 May 2016 20:33:45 +0200 Subject: HSI: omap_ssi_port: prepare start_tx/stop_tx for blocking pm_runtime calls ssi_start_tx and ssi_stop_tx may be called from atomic context. Once pm_runtime_irq_safe() is removed for omap-ssi, this will fail, due to blocking pm_runtime_*_sync() calls. This fixes ssi_stop_tx by using non-sync API and ssi_start_tx by using a worker thread. Signed-off-by: Sebastian Reichel Tested-by: Pavel Machek --- drivers/hsi/controllers/omap_ssi.h | 2 ++ drivers/hsi/controllers/omap_ssi_port.c | 23 ++++++++++++++++++----- 2 files changed, 20 insertions(+), 5 deletions(-) (limited to 'drivers/hsi') diff --git a/drivers/hsi/controllers/omap_ssi.h b/drivers/hsi/controllers/omap_ssi.h index 6cdaad8..5467f61 100644 --- a/drivers/hsi/controllers/omap_ssi.h +++ b/drivers/hsi/controllers/omap_ssi.h @@ -79,6 +79,7 @@ struct omap_ssm_ctx { * @pio_tasklet: Bottom half for PIO transfers and events * @flags: flags to keep track of states * @wk_refcount: Reference count for output wake line + * @work: worker for starting TX * @sys_mpu_enable: Context for the interrupt enable register for irq 0 * @sst: Context for the synchronous serial transmitter * @ssr: Context for the synchronous serial receiver @@ -103,6 +104,7 @@ struct omap_ssi_port { bool wktest:1; /* FIXME: HACK to be removed */ unsigned long flags; unsigned int wk_refcount; + struct work_struct work; /* OMAP SSI port context */ u32 sys_mpu_enable; /* We use only one irq */ struct omap_ssm_ctx sst; diff --git a/drivers/hsi/controllers/omap_ssi_port.c b/drivers/hsi/controllers/omap_ssi_port.c index 0d34523..cc56d0e 100644 --- a/drivers/hsi/controllers/omap_ssi_port.c +++ b/drivers/hsi/controllers/omap_ssi_port.c @@ -567,12 +567,22 @@ static int ssi_flush(struct hsi_client *cl) return 0; } +static void start_tx_work(struct work_struct *work) +{ + struct omap_ssi_port *omap_port = + container_of(work, struct omap_ssi_port, work); + struct hsi_port *port = to_hsi_port(omap_port->dev); + struct hsi_controller *ssi = to_hsi_controller(port->device.parent); + struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi); + + pm_runtime_get_sync(omap_port->pdev); /* Grab clocks */ + writel(SSI_WAKE(0), omap_ssi->sys + SSI_SET_WAKE_REG(port->num)); +} + static int ssi_start_tx(struct hsi_client *cl) { struct hsi_port *port = hsi_get_port(cl); struct omap_ssi_port *omap_port = hsi_port_drvdata(port); - struct hsi_controller *ssi = to_hsi_controller(port->device.parent); - struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi); dev_dbg(&port->device, "Wake out high %d\n", omap_port->wk_refcount); @@ -581,10 +591,10 @@ static int ssi_start_tx(struct hsi_client *cl) spin_unlock_bh(&omap_port->wk_lock); return 0; } - pm_runtime_get_sync(omap_port->pdev); /* Grab clocks */ - writel(SSI_WAKE(0), omap_ssi->sys + SSI_SET_WAKE_REG(port->num)); spin_unlock_bh(&omap_port->wk_lock); + schedule_work(&omap_port->work); + return 0; } @@ -604,9 +614,10 @@ static int ssi_stop_tx(struct hsi_client *cl) return 0; } writel(SSI_WAKE(0), omap_ssi->sys + SSI_CLEAR_WAKE_REG(port->num)); - pm_runtime_put_sync(omap_port->pdev); /* Release clocks */ spin_unlock_bh(&omap_port->wk_lock); + pm_runtime_put(omap_port->pdev); /* Release clocks */ + return 0; } @@ -1149,6 +1160,8 @@ static int ssi_port_probe(struct platform_device *pd) omap_port->pdev = &pd->dev; omap_port->port_id = port_id; + INIT_WORK(&omap_port->work, start_tx_work); + /* initialize HSI port */ port->async = ssi_async; port->setup = ssi_setup; -- cgit v1.1