From: Samuel Holland samuel@sholland.org
[ Upstream commit 077686da0e2162c4ea5ae0df205849c2a7a84479 ]
When communicating with a PMIC during system poweroff (pm_power_off()), IRQs are disabled and we are in a RCU read-side critical section, so we cannot use wait_for_completion_io_timeout(). Instead, poll the status register for transfer completion.
Fixes: d787dcdb9c8f ("bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus") Signed-off-by: Samuel Holland samuel@sholland.org Reviewed-by: Jernej Skrabec jernej.skrabec@gmail.com Link: https://lore.kernel.org/r/20221114015749.28490-3-samuel@sholland.org Signed-off-by: Jernej Skrabec jernej.skrabec@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/bus/sunxi-rsb.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-)
diff --git a/drivers/bus/sunxi-rsb.c b/drivers/bus/sunxi-rsb.c index 17343cd75338..3aa91aed3bf7 100644 --- a/drivers/bus/sunxi-rsb.c +++ b/drivers/bus/sunxi-rsb.c @@ -267,6 +267,9 @@ EXPORT_SYMBOL_GPL(sunxi_rsb_driver_register); /* common code that starts a transfer */ static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb) { + u32 int_mask, status; + bool timeout; + if (readl(rsb->regs + RSB_CTRL) & RSB_CTRL_START_TRANS) { dev_dbg(rsb->dev, "RSB transfer still in progress\n"); return -EBUSY; @@ -274,13 +277,23 @@ static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb)
reinit_completion(&rsb->complete);
- writel(RSB_INTS_LOAD_BSY | RSB_INTS_TRANS_ERR | RSB_INTS_TRANS_OVER, - rsb->regs + RSB_INTE); + int_mask = RSB_INTS_LOAD_BSY | RSB_INTS_TRANS_ERR | RSB_INTS_TRANS_OVER; + writel(int_mask, rsb->regs + RSB_INTE); writel(RSB_CTRL_START_TRANS | RSB_CTRL_GLOBAL_INT_ENB, rsb->regs + RSB_CTRL);
- if (!wait_for_completion_io_timeout(&rsb->complete, - msecs_to_jiffies(100))) { + if (irqs_disabled()) { + timeout = readl_poll_timeout_atomic(rsb->regs + RSB_INTS, + status, (status & int_mask), + 10, 100000); + writel(status, rsb->regs + RSB_INTS); + } else { + timeout = !wait_for_completion_io_timeout(&rsb->complete, + msecs_to_jiffies(100)); + status = rsb->status; + } + + if (timeout) { dev_dbg(rsb->dev, "RSB timeout\n");
/* abort the transfer */ @@ -292,18 +305,18 @@ static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb) return -ETIMEDOUT; }
- if (rsb->status & RSB_INTS_LOAD_BSY) { + if (status & RSB_INTS_LOAD_BSY) { dev_dbg(rsb->dev, "RSB busy\n"); return -EBUSY; }
- if (rsb->status & RSB_INTS_TRANS_ERR) { - if (rsb->status & RSB_INTS_TRANS_ERR_ACK) { + if (status & RSB_INTS_TRANS_ERR) { + if (status & RSB_INTS_TRANS_ERR_ACK) { dev_dbg(rsb->dev, "RSB slave nack\n"); return -EINVAL; }
- if (rsb->status & RSB_INTS_TRANS_ERR_DATA) { + if (status & RSB_INTS_TRANS_ERR_DATA) { dev_dbg(rsb->dev, "RSB transfer data error\n"); return -EIO; }