diff options
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/8250/8250_omap.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 6aaa84355fd11..1b337fee07ed1 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -1110,13 +1110,14 @@ static int omap8250_no_handle_irq(struct uart_port *port) return 0; } +static const u8 omap4_habit = UART_ERRATA_CLOCK_DISABLE; static const u8 am3352_habit = OMAP_DMA_TX_KICK | UART_ERRATA_CLOCK_DISABLE; static const u8 dra742_habit = UART_ERRATA_CLOCK_DISABLE; static const struct of_device_id omap8250_dt_ids[] = { { .compatible = "ti,omap2-uart" }, { .compatible = "ti,omap3-uart" }, - { .compatible = "ti,omap4-uart" }, + { .compatible = "ti,omap4-uart", .data = &omap4_habit, }, { .compatible = "ti,am3352-uart", .data = &am3352_habit, }, { .compatible = "ti,am4372-uart", .data = &am3352_habit, }, { .compatible = "ti,dra742-uart", .data = &dra742_habit, }, @@ -1362,6 +1363,19 @@ static int omap8250_soft_reset(struct device *dev) int sysc; int syss; + /* + * At least on omap4, unused uarts may not idle after reset without + * a basic scr dma configuration even with no dma in use. The + * module clkctrl status bits will be 1 instead of 3 blocking idle + * for the whole clockdomain. The softreset below will clear scr, + * and we restore it on resume so this is safe to do on all SoCs + * needing omap8250_soft_reset() quirk. Do it in two writes as + * recommended in the comment for omap8250_update_scr(). + */ + serial_out(up, UART_OMAP_SCR, OMAP_UART_SCR_DMAMODE_1); + serial_out(up, UART_OMAP_SCR, + OMAP_UART_SCR_DMAMODE_1 | OMAP_UART_SCR_DMAMODE_CTL); + sysc = serial_in(up, UART_OMAP_SYSC); /* softreset the UART */ |