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Diffstat (limited to 'arch/powerpc/platforms/52xx/mpc52xx_common.c')
-rw-r--r--arch/powerpc/platforms/52xx/mpc52xx_common.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/52xx/mpc52xx_common.c b/arch/powerpc/platforms/52xx/mpc52xx_common.c
index a46bad0c2339..6e905314ad5d 100644
--- a/arch/powerpc/platforms/52xx/mpc52xx_common.c
+++ b/arch/powerpc/platforms/52xx/mpc52xx_common.c
@@ -12,9 +12,11 @@
#undef DEBUG
+#include <linux/gpio.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/mpc52xx.h>
@@ -82,6 +84,14 @@ mpc5200_setup_xlb_arbiter(void)
iounmap(xlb);
}
+/*
+ * This variable is mapped in mpc52xx_map_common_devices and
+ * used in mpc5200_psc_ac97_gpio_reset().
+ */
+static DEFINE_SPINLOCK(gpio_lock);
+struct mpc52xx_gpio __iomem *simple_gpio;
+struct mpc52xx_gpio_wkup __iomem *wkup_gpio;
+
/**
* mpc52xx_declare_of_platform_devices: register internal devices and children
* of the localplus bus to the of_platform
@@ -109,6 +119,15 @@ static struct of_device_id mpc52xx_cdm_ids[] __initdata = {
{ .compatible = "mpc5200-cdm", }, /* old */
{}
};
+static const struct of_device_id mpc52xx_gpio_simple[] = {
+ { .compatible = "fsl,mpc5200-gpio", },
+ {}
+};
+static const struct of_device_id mpc52xx_gpio_wkup[] = {
+ { .compatible = "fsl,mpc5200-gpio-wkup", },
+ {}
+};
+
/**
* mpc52xx_map_common_devices: iomap devices required by common code
@@ -135,6 +154,16 @@ mpc52xx_map_common_devices(void)
np = of_find_matching_node(NULL, mpc52xx_cdm_ids);
mpc52xx_cdm = of_iomap(np, 0);
of_node_put(np);
+
+ /* simple_gpio registers */
+ np = of_find_matching_node(NULL, mpc52xx_gpio_simple);
+ simple_gpio = of_iomap(np, 0);
+ of_node_put(np);
+
+ /* wkup_gpio registers */
+ np = of_find_matching_node(NULL, mpc52xx_gpio_wkup);
+ wkup_gpio = of_iomap(np, 0);
+ of_node_put(np);
}
/**
@@ -233,3 +262,80 @@ mpc52xx_restart(char *cmd)
while (1);
}
+
+#define PSC1_RESET 0x1
+#define PSC1_SYNC 0x4
+#define PSC1_SDATA_OUT 0x1
+#define PSC2_RESET 0x2
+#define PSC2_SYNC (0x4<<4)
+#define PSC2_SDATA_OUT (0x1<<4)
+#define MPC52xx_GPIO_PSC1_MASK 0x7
+#define MPC52xx_GPIO_PSC2_MASK (0x7<<4)
+
+/**
+ * mpc5200_psc_ac97_gpio_reset: Use gpio pins to reset the ac97 bus
+ *
+ * @psc: psc number to reset (only psc 1 and 2 support ac97)
+ */
+int mpc5200_psc_ac97_gpio_reset(int psc_number)
+{
+ unsigned long flags;
+ u32 gpio;
+ u32 mux;
+ int out;
+ int reset;
+ int sync;
+
+ if ((!simple_gpio) || (!wkup_gpio))
+ return -ENODEV;
+
+ switch (psc_number) {
+ case 0:
+ reset = PSC1_RESET; /* AC97_1_RES */
+ sync = PSC1_SYNC; /* AC97_1_SYNC */
+ out = PSC1_SDATA_OUT; /* AC97_1_SDATA_OUT */
+ gpio = MPC52xx_GPIO_PSC1_MASK;
+ break;
+ case 1:
+ reset = PSC2_RESET; /* AC97_2_RES */
+ sync = PSC2_SYNC; /* AC97_2_SYNC */
+ out = PSC2_SDATA_OUT; /* AC97_2_SDATA_OUT */
+ gpio = MPC52xx_GPIO_PSC2_MASK;
+ break;
+ default:
+ pr_err(__FILE__ ": Unable to determine PSC, no ac97 "
+ "cold-reset will be performed\n");
+ return -ENODEV;
+ }
+
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ /* Reconfiure pin-muxing to gpio */
+ mux = in_be32(&simple_gpio->port_config);
+ out_be32(&simple_gpio->port_config, mux & (~gpio));
+
+ /* enable gpio pins for output */
+ setbits8(&wkup_gpio->wkup_gpioe, reset);
+ setbits32(&simple_gpio->simple_gpioe, sync | out);
+
+ setbits8(&wkup_gpio->wkup_ddr, reset);
+ setbits32(&simple_gpio->simple_ddr, sync | out);
+
+ /* Assert cold reset */
+ clrbits32(&simple_gpio->simple_dvo, sync | out);
+ clrbits8(&wkup_gpio->wkup_dvo, reset);
+
+ /* wait at lease 1 us */
+ udelay(2);
+
+ /* Deassert reset */
+ setbits8(&wkup_gpio->wkup_dvo, reset);
+
+ /* Restore pin-muxing */
+ out_be32(&simple_gpio->port_config, mux);
+
+ spin_unlock_irqrestore(&gpio_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(mpc5200_psc_ac97_gpio_reset);