diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c index 4d55090fa443..15e9d3ef8839 100644 --- a/drivers/spi/spi-zynqmp-gqspi.c +++ b/drivers/spi/spi-zynqmp-gqspi.c @@ -1373,11 +1373,45 @@ static void zynqmp_qspi_remove(struct platform_device *pdev) clk_disable_unprepare(xqspi->pclk); } +static void zynqmp_qspi_shutdown(struct platform_device *pdev) +{ + struct zynqmp_qspi *xqspi = platform_get_drvdata(pdev); + int ret; + + /* + * Stop the queue and reject any later transfer first, so the write + * below cannot cut into a message that is still being executed. + * Unlike ->suspend this cannot abort on error: a controller left + * mastering the bus is worse than a truncated transfer. + */ + ret = spi_controller_suspend(xqspi->ctlr); + if (ret) + dev_warn(&pdev->dev, "could not stop the queue: %d\n", ret); + + /* + * Only a runtime suspended controller can be left alone: its clocks + * are gated, so it cannot be mastering the bus, and its registers + * must not be accessed either. Any other answer means it may be + * running and has to be stopped. In particular, on a kernel built + * without runtime PM this returns -EINVAL, and there the clocks + * enabled in probe() are never gated at all. + */ + ret = pm_runtime_get_if_in_use(&pdev->dev); + if (!ret) + return; + + zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0); + + if (ret > 0) + pm_runtime_put_noidle(&pdev->dev); +} + MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match); static struct platform_driver zynqmp_qspi_driver = { .probe = zynqmp_qspi_probe, .remove = zynqmp_qspi_remove, + .shutdown = zynqmp_qspi_shutdown, .driver = { .name = "zynqmp-qspi", .of_match_table = zynqmp_qspi_of_match,