HSI: omap_ssi_port: switch to threaded pio irq
Move pio interrupt handler from tasklet into thread to
allow runtime_pm_get_sync calls without irq_safe being
set.
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Tested-by: Pavel Machek <pavel@ucw.cz>
diff --git a/drivers/hsi/controllers/omap_ssi.h b/drivers/hsi/controllers/omap_ssi.h
index 5467f61..99143f4 100644
--- a/drivers/hsi/controllers/omap_ssi.h
+++ b/drivers/hsi/controllers/omap_ssi.h
@@ -76,7 +76,6 @@
* @irq: IRQ number
* @wake_irq: IRQ number for incoming wake line (-1 if none)
* @wake_gpio: GPIO number for incoming wake line (-1 if none)
- * @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
@@ -100,7 +99,6 @@
unsigned int irq;
int wake_irq;
struct gpio_desc *wake_gpio;
- struct tasklet_struct pio_tasklet;
bool wktest:1; /* FIXME: HACK to be removed */
unsigned long flags;
unsigned int wk_refcount;
diff --git a/drivers/hsi/controllers/omap_ssi_port.c b/drivers/hsi/controllers/omap_ssi_port.c
index cc56d0e..f62f0c4 100644
--- a/drivers/hsi/controllers/omap_ssi_port.c
+++ b/drivers/hsi/controllers/omap_ssi_port.c
@@ -877,7 +877,7 @@
u32 reg;
u32 val;
- spin_lock(&omap_port->lock);
+ spin_lock_bh(&omap_port->lock);
msg = list_first_entry(queue, struct hsi_msg, link);
if ((!msg->sgt.nents) || (!msg->sgt.sgl->length)) {
msg->actual_len = 0;
@@ -909,7 +909,7 @@
(msg->ttype == HSI_MSG_WRITE))) {
writel(val, omap_ssi->sys +
SSI_MPU_STATUS_REG(port->num, 0));
- spin_unlock(&omap_port->lock);
+ spin_unlock_bh(&omap_port->lock);
return;
}
@@ -925,12 +925,12 @@
writel_relaxed(reg, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
writel_relaxed(val, omap_ssi->sys + SSI_MPU_STATUS_REG(port->num, 0));
list_del(&msg->link);
- spin_unlock(&omap_port->lock);
+ spin_unlock_bh(&omap_port->lock);
msg->complete(msg);
ssi_transfer(omap_port, queue);
}
-static void ssi_pio_tasklet(unsigned long ssi_port)
+static irqreturn_t ssi_pio_thread(int irq, void *ssi_port)
{
struct hsi_port *port = (struct hsi_port *)ssi_port;
struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
@@ -941,37 +941,29 @@
u32 status_reg;
pm_runtime_get_sync(omap_port->pdev);
- status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
- status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
- for (ch = 0; ch < omap_port->channels; ch++) {
- if (status_reg & SSI_DATAACCEPT(ch))
- ssi_pio_complete(port, &omap_port->txqueue[ch]);
- if (status_reg & SSI_DATAAVAILABLE(ch))
- ssi_pio_complete(port, &omap_port->rxqueue[ch]);
- }
- if (status_reg & SSI_BREAKDETECTED)
- ssi_break_complete(port);
- if (status_reg & SSI_ERROROCCURED)
- ssi_error(port);
+ do {
+ status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
+ status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
- status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
- status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
- pm_runtime_put_sync(omap_port->pdev);
+ for (ch = 0; ch < omap_port->channels; ch++) {
+ if (status_reg & SSI_DATAACCEPT(ch))
+ ssi_pio_complete(port, &omap_port->txqueue[ch]);
+ if (status_reg & SSI_DATAAVAILABLE(ch))
+ ssi_pio_complete(port, &omap_port->rxqueue[ch]);
+ }
+ if (status_reg & SSI_BREAKDETECTED)
+ ssi_break_complete(port);
+ if (status_reg & SSI_ERROROCCURED)
+ ssi_error(port);
- if (status_reg)
- tasklet_hi_schedule(&omap_port->pio_tasklet);
- else
- enable_irq(omap_port->irq);
-}
+ status_reg = readl(sys + SSI_MPU_STATUS_REG(port->num, 0));
+ status_reg &= readl(sys + SSI_MPU_ENABLE_REG(port->num, 0));
-static irqreturn_t ssi_pio_isr(int irq, void *port)
-{
- struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
+ /* TODO: sleep if we retry? */
+ } while (status_reg);
- tasklet_hi_schedule(&omap_port->pio_tasklet);
- disable_irq_nosync(irq);
-
+ pm_runtime_put(omap_port->pdev);
return IRQ_HANDLED;
}
@@ -1023,10 +1015,8 @@
return err;
}
omap_port->irq = err;
- tasklet_init(&omap_port->pio_tasklet, ssi_pio_tasklet,
- (unsigned long)port);
- err = devm_request_irq(&port->device, omap_port->irq, ssi_pio_isr,
- 0, "mpu_irq0", port);
+ err = devm_request_threaded_irq(&port->device, omap_port->irq, NULL,
+ ssi_pio_thread, IRQF_ONESHOT, "SSI PORT", port);
if (err < 0)
dev_err(&port->device, "Request IRQ %d failed (%d)\n",
omap_port->irq, err);
@@ -1229,8 +1219,6 @@
hsi_port_unregister_clients(port);
- tasklet_kill(&omap_port->pio_tasklet);
-
port->async = hsi_dummy_msg;
port->setup = hsi_dummy_cl;
port->flush = hsi_dummy_cl;