serial: sh-sci: Handle GPIO function requests.
This adds initial support for requesting the various GPIO functions
necessary for certain ports. This just plugs in dumb request/free logic,
but serves as a building block for migrating off of the ->init_pins mess
to a wholly gpiolib backed solution (primarily parts with external
RTS/CTS pins, but will also allow us to clean up RXD pin testing).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 761a800..9e62349 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -50,6 +50,7 @@
#include <linux/dma-mapping.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
+#include <linux/gpio.h>
#ifdef CONFIG_SUPERH
#include <asm/sh_bios.h>
@@ -73,6 +74,7 @@
struct clk *fclk;
char *irqstr[SCIx_NR_IRQS];
+ char *gpiostr[SCIx_NR_FNS];
struct dma_chan *chan_tx;
struct dma_chan *chan_rx;
@@ -1105,6 +1107,67 @@
}
}
+static const char *sci_gpio_names[SCIx_NR_FNS] = {
+ "sck", "rxd", "txd", "cts", "rts",
+};
+
+static const char *sci_gpio_str(unsigned int index)
+{
+ return sci_gpio_names[index];
+}
+
+static void __devinit sci_init_gpios(struct sci_port *port)
+{
+ struct uart_port *up = &port->port;
+ int i;
+
+ if (!port->cfg)
+ return;
+
+ for (i = 0; i < SCIx_NR_FNS; i++) {
+ const char *desc;
+ int ret;
+
+ if (!port->cfg->gpios[i])
+ continue;
+
+ desc = sci_gpio_str(i);
+
+ port->gpiostr[i] = kasprintf(GFP_KERNEL, "%s:%s",
+ dev_name(up->dev), desc);
+
+ /*
+ * If we've failed the allocation, we can still continue
+ * on with a NULL string.
+ */
+ if (!port->gpiostr[i])
+ dev_notice(up->dev, "%s string allocation failure\n",
+ desc);
+
+ ret = gpio_request(port->cfg->gpios[i], port->gpiostr[i]);
+ if (unlikely(ret != 0)) {
+ dev_notice(up->dev, "failed %s gpio request\n", desc);
+
+ /*
+ * If we can't get the GPIO for whatever reason,
+ * no point in keeping the verbose string around.
+ */
+ kfree(port->gpiostr[i]);
+ }
+ }
+}
+
+static void sci_free_gpios(struct sci_port *port)
+{
+ int i;
+
+ for (i = 0; i < SCIx_NR_FNS; i++)
+ if (port->cfg->gpios[i]) {
+ gpio_free(port->cfg->gpios[i]);
+ kfree(port->gpiostr[i]);
+ }
+}
+
static unsigned int sci_tx_empty(struct uart_port *port)
{
unsigned short status = sci_in(port, SCxSR);
@@ -1962,6 +2025,8 @@
struct uart_port *port = &sci_port->port;
int ret;
+ sci_port->cfg = p;
+
port->ops = &sci_uart_ops;
port->iotype = UPIO_MEM;
port->line = index;
@@ -2007,6 +2072,8 @@
port->dev = &dev->dev;
+ sci_init_gpios(sci_port);
+
pm_runtime_irq_safe(&dev->dev);
pm_runtime_enable(&dev->dev);
}
@@ -2041,8 +2108,6 @@
p->error_mask |= (1 << p->overrun_bit);
}
- sci_port->cfg = p;
-
port->mapbase = p->mapbase;
port->type = p->type;
port->flags = p->flags;
@@ -2249,6 +2314,8 @@
cpufreq_unregister_notifier(&port->freq_transition,
CPUFREQ_TRANSITION_NOTIFIER);
+ sci_free_gpios(port);
+
uart_remove_one_port(&sci_uart_driver, &port->port);
clk_put(port->iclk);