[PATCH 6/9] serial: 8250_dw: Support clk framework also with ACPI

From: Heikki Krogerus
Date: Wed Apr 10 2013 - 10:00:38 EST


The Lynxpoint LPSS peripheral clocks are now handled in clk
framework so the drivers do not need to take care of them
manually. In dw8250_probe_acpi(), the uartclk is now taken
from the driver_data only if it was not already set.

Signed-off-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
---
drivers/tty/serial/8250/8250_dw.c | 18 +++++-------------
1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index d6aea85..de7a186 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -36,9 +36,6 @@
#define DW_UART_CPR 0xf4 /* Component Parameter Register */
#define DW_UART_UCV 0xf8 /* UART Component Version */

-/* Intel Low Power Subsystem specific */
-#define LPSS_PRV_CLOCK_PARAMS 0x800
-
/* Component Parameter Register bits */
#define DW_UART_CPR_ABP_DATA_WIDTH (3 << 0)
#define DW_UART_CPR_AFCE_MODE (1 << 4)
@@ -226,7 +223,6 @@ static int dw8250_probe_acpi(struct uart_port *p)
{
const struct acpi_device_id *id;
acpi_status status;
- u32 reg;

id = acpi_match_device(p->dev->driver->acpi_match_table, p->dev);
if (!id)
@@ -236,7 +232,9 @@ static int dw8250_probe_acpi(struct uart_port *p)
p->serial_in = dw8250_serial_in32;
p->serial_out = dw8250_serial_out32;
p->regshift = 2;
- p->uartclk = (unsigned int)id->driver_data;
+
+ if (!p->uartclk)
+ p->uartclk = (unsigned int)id->driver_data;

status = acpi_walk_resources(ACPI_HANDLE(p->dev), METHOD_NAME__CRS,
dw8250_acpi_walk_resource, p);
@@ -246,12 +244,6 @@ static int dw8250_probe_acpi(struct uart_port *p)
return -ENODEV;
}

- /* Fix Haswell issue where the clocks do not get enabled */
- if (!strcmp(id->id, "INT33C4") || !strcmp(id->id, "INT33C5")) {
- reg = readl(p->membase + LPSS_PRV_CLOCK_PARAMS);
- writel(reg | 1, p->membase + LPSS_PRV_CLOCK_PARAMS);
- }
-
return 0;
}
#else
@@ -425,8 +417,8 @@ static const struct of_device_id dw8250_of_match[] = {
MODULE_DEVICE_TABLE(of, dw8250_of_match);

static const struct acpi_device_id dw8250_acpi_match[] = {
- { "INT33C4", 100000000 },
- { "INT33C5", 100000000 },
+ { "INT33C4", 0 },
+ { "INT33C5", 0 },
{ },
};
MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match);
--
1.7.10.4

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