diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_mtk.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_mtk.c | 50 |
1 files changed, 32 insertions, 18 deletions
diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c index 4d067f515f74..f839380c2f4c 100644 --- a/drivers/tty/serial/8250/8250_mtk.c +++ b/drivers/tty/serial/8250/8250_mtk.c @@ -32,6 +32,7 @@ #define MTK_UART_RXTRI_AD 0x14 /* RX Trigger address */ #define MTK_UART_FRACDIV_L 0x15 /* Fractional divider LSB address */ #define MTK_UART_FRACDIV_M 0x16 /* Fractional divider MSB address */ +#define MTK_UART_DEBUG0 0x18 #define MTK_UART_IER_XOFFI 0x20 /* Enable XOFF character interrupt */ #define MTK_UART_IER_RTSI 0x40 /* Enable RTS Modem status interrupt */ #define MTK_UART_IER_CTSI 0x80 /* Enable CTS Modem status interrupt */ @@ -388,9 +389,18 @@ mtk8250_set_termios(struct uart_port *port, struct ktermios *termios, static int __maybe_unused mtk8250_runtime_suspend(struct device *dev) { struct mtk8250_data *data = dev_get_drvdata(dev); + struct uart_8250_port *up = serial8250_get_port(data->line); - clk_disable_unprepare(data->uart_clk); - clk_disable_unprepare(data->bus_clk); + /* wait until UART in idle status */ + while + (serial_in(up, MTK_UART_DEBUG0)); + + if (data->clk_count == 0U) { + dev_dbg(dev, "%s clock count is 0\n", __func__); + } else { + clk_disable_unprepare(data->bus_clk); + data->clk_count--; + } return 0; } @@ -400,16 +410,16 @@ static int __maybe_unused mtk8250_runtime_resume(struct device *dev) struct mtk8250_data *data = dev_get_drvdata(dev); int err; - err = clk_prepare_enable(data->uart_clk); - if (err) { - dev_warn(dev, "Can't enable clock\n"); - return err; - } - - err = clk_prepare_enable(data->bus_clk); - if (err) { - dev_warn(dev, "Can't enable bus clock\n"); - return err; + if (data->clk_count > 0U) { + dev_dbg(dev, "%s clock count is %d\n", __func__, + data->clk_count); + } else { + err = clk_prepare_enable(data->bus_clk); + if (err) { + dev_warn(dev, "Can't enable bus clock\n"); + return err; + } + data->clk_count++; } return 0; @@ -419,12 +429,14 @@ static void mtk8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old) { if (!state) - pm_runtime_get_sync(port->dev); + if (!mtk8250_runtime_resume(port->dev)) + pm_runtime_get_sync(port->dev); serial8250_do_pm(port, state, old); if (state) - pm_runtime_put_sync_suspend(port->dev); + if (!pm_runtime_put_sync_suspend(port->dev)) + mtk8250_runtime_suspend(port->dev); } #ifdef CONFIG_SERIAL_8250_DMA @@ -501,6 +513,8 @@ static int mtk8250_probe(struct platform_device *pdev) if (!data) return -ENOMEM; + data->clk_count = 0; + if (pdev->dev.of_node) { err = mtk8250_probe_of(pdev, &uart.port, data); if (err) @@ -533,6 +547,7 @@ static int mtk8250_probe(struct platform_device *pdev) platform_set_drvdata(pdev, data); + pm_runtime_enable(&pdev->dev); err = mtk8250_runtime_resume(&pdev->dev); if (err) return err; @@ -541,9 +556,6 @@ static int mtk8250_probe(struct platform_device *pdev) if (data->line < 0) return data->line; - pm_runtime_set_active(&pdev->dev); - pm_runtime_enable(&pdev->dev); - data->rx_wakeup_irq = platform_get_irq_optional(pdev, 1); return 0; @@ -556,11 +568,13 @@ static int mtk8250_remove(struct platform_device *pdev) pm_runtime_get_sync(&pdev->dev); serial8250_unregister_port(data->line); - mtk8250_runtime_suspend(&pdev->dev); pm_runtime_disable(&pdev->dev); pm_runtime_put_noidle(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + mtk8250_runtime_suspend(&pdev->dev); + return 0; } |