2008-03-26 21:41:28

by Florian Fainelli

[permalink] [raw]
Subject: [PATCH] [x86] rdc321x: GPIO routines bugfixes

Hi Ingo,

This should be in 2.6.25 if possible. Thanks !
--
From: Florian Fainelli <[email protected]>
Subject: [PATCH] [x86] rdc321x: GPIO routines bugfixes

This patch fixes the use of GPIO routines which are in the PCI
configuration space of the RDC321x, therefore reading/writing
to this space without spinlock protection can be problematic.

We also now request and free GPIOs and support the MGB100
board, previous code was very AR525W-centric.

Signed-off-by: Volker Weiss <[email protected]>
Signed-off-by: Florian Fainelli <[email protected]>
---
diff --git a/arch/x86/mach-rdc321x/gpio.c b/arch/x86/mach-rdc321x/gpio.c
index 0312691..247f33d 100644
--- a/arch/x86/mach-rdc321x/gpio.c
+++ b/arch/x86/mach-rdc321x/gpio.c
@@ -1,91 +1,194 @@
/*
- * Copyright (C) 2007, OpenWrt.org, Florian Fainelli <[email protected]>
- * RDC321x architecture specific GPIO support
+ * GPIO support for RDC SoC R3210/R8610
+ *
+ * Copyright (C) 2007, Florian Fainelli <[email protected]>
+ * Copyright (C) 2008, Volker Weiss <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version.
*/

-#include <linux/autoconf.h>
-#include <linux/init.h>
+
+#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/types.h>
#include <linux/module.h>
-#include <linux/delay.h>

+#include <asm/gpio.h>
#include <asm/mach-rdc321x/rdc321x_defs.h>

-static inline int rdc_gpio_is_valid(unsigned gpio)
+
+/* spin lock to protect our private copy of GPIO data register plus
+ the access to PCI conf registers. */
+static DEFINE_SPINLOCK(gpio_lock);
+
+/* copy of GPIO data registers */
+static u32 gpio_data_reg1;
+static u32 gpio_data_reg2;
+
+static u32 gpio_request_data[2];
+
+
+static inline void rdc321x_conf_write(unsigned addr, u32 value)
{
- return (gpio <= RDC_MAX_GPIO);
+ outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR);
+ outl(value, RDC3210_CFGREG_DATA);
}

-static unsigned int rdc_gpio_read(unsigned gpio)
+static inline void rdc321x_conf_or(unsigned addr, u32 value)
{
- unsigned int val;
-
- val = 0x80000000 | (7 << 11) | ((gpio&0x20?0x84:0x48));
- outl(val, RDC3210_CFGREG_ADDR);
- udelay(10);
- val = inl(RDC3210_CFGREG_DATA);
- val |= (0x1 << (gpio & 0x1F));
- outl(val, RDC3210_CFGREG_DATA);
- udelay(10);
- val = 0x80000000 | (7 << 11) | ((gpio&0x20?0x88:0x4C));
- outl(val, RDC3210_CFGREG_ADDR);
- udelay(10);
- val = inl(RDC3210_CFGREG_DATA);
-
- return val;
+ outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR);
+ value |= inl(RDC3210_CFGREG_DATA);
+ outl(value, RDC3210_CFGREG_DATA);
}

-static void rdc_gpio_write(unsigned int val)
+static inline u32 rdc321x_conf_read(unsigned addr)
{
- if (val) {
- outl(val, RDC3210_CFGREG_DATA);
- udelay(10);
- }
+ outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR);
+
+ return inl(RDC3210_CFGREG_DATA);
}

-int rdc_gpio_get_value(unsigned gpio)
+/* configure pin as GPIO */
+static void rdc321x_configure_gpio(unsigned gpio)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&gpio_lock, flags);
+ rdc321x_conf_or(gpio < 32
+ ? RDC321X_GPIO_CTRL_REG1 : RDC321X_GPIO_CTRL_REG2,
+ 1 << (gpio & 0x1f));
+ spin_unlock_irqrestore(&gpio_lock, flags);
+}
+
+/* initially setup the 2 copies of the gpio data registers.
+ This function must be called by the platform setup code. */
+void __init rdc321x_gpio_setup()
+{
+ /* this might not be, what others (BIOS, bootloader, etc.)
+ wrote to these registers before, but it's a good guess. Still
+ better than just using 0xffffffff. */
+
+ gpio_data_reg1 = rdc321x_conf_read(RDC321X_GPIO_DATA_REG1);
+ gpio_data_reg2 = rdc321x_conf_read(RDC321X_GPIO_DATA_REG2);
+}
+
+/* determine, if gpio number is valid */
+static inline int rdc321x_is_gpio(unsigned gpio)
+{
+ return gpio <= RDC321X_MAX_GPIO;
+}
+
+/* request GPIO */
+int rdc_gpio_request(unsigned gpio, const char *label)
{
- if (rdc_gpio_is_valid(gpio))
- return (int)rdc_gpio_read(gpio);
- else
+ unsigned long flags;
+
+ if (!rdc321x_is_gpio(gpio))
return -EINVAL;
+
+ spin_lock_irqsave(&gpio_lock, flags);
+ if (gpio_request_data[(gpio & 0x20) ? 1 : 0] & (1 << (gpio & 0x1f)))
+ goto inuse;
+ gpio_request_data[(gpio & 0x20) ? 1 : 0] |= (1 << (gpio & 0x1f));
+ spin_unlock_irqrestore(&gpio_lock, flags);
+
+ return 0;
+inuse:
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ return -EINVAL;
}
-EXPORT_SYMBOL(rdc_gpio_get_value);
+EXPORT_SYMBOL(rdc_gpio_request);

-void rdc_gpio_set_value(unsigned gpio, int value)
+/* release previously-claimed GPIO */
+void rdc_gpio_free(unsigned gpio)
{
- unsigned int val;
+ unsigned long flags;

- if (!rdc_gpio_is_valid(gpio))
+ if (!rdc321x_is_gpio(gpio))
return;

- val = rdc_gpio_read(gpio);
+ spin_lock_irqsave(&gpio_lock, flags);
+ gpio_request_data[(gpio & 0x20) ? 1 : 0] &= ~(1 << (gpio & 0x1f));
+ spin_unlock_irqrestore(&gpio_lock, flags);
+}
+EXPORT_SYMBOL(rdc_gpio_free);
+
+/* read GPIO pin */
+int rdc_gpio_get_value(unsigned gpio)
+{
+ u32 reg;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gpio_lock, flags);
+ reg = rdc321x_conf_read(gpio < 32
+ ? RDC321X_GPIO_DATA_REG1 : RDC321X_GPIO_DATA_REG2);
+ spin_unlock_irqrestore(&gpio_lock, flags);

- if (value)
- val &= ~(0x1 << (gpio & 0x1F));
- else
- val |= (0x1 << (gpio & 0x1F));
+ return (1 << (gpio & 0x1f)) & reg ? 1 : 0;
+}
+EXPORT_SYMBOL(rdc_gpio_get_value);

- rdc_gpio_write(val);
+/* set GPIO pin to value */
+void rdc_gpio_set_value(unsigned gpio, int value)
+{
+ unsigned long flags;
+ u32 reg;
+
+ reg = 1 << (gpio & 0x1f);
+ if (gpio < 32) {
+ spin_lock_irqsave(&gpio_lock, flags);
+ if (value)
+ gpio_data_reg1 |= reg;
+ else
+ gpio_data_reg1 &= ~reg;
+ rdc321x_conf_write(RDC321X_GPIO_DATA_REG1, gpio_data_reg1);
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ } else {
+ spin_lock_irqsave(&gpio_lock, flags);
+ if (value)
+ gpio_data_reg2 |= reg;
+ else
+ gpio_data_reg2 &= ~reg;
+ rdc321x_conf_write(RDC321X_GPIO_DATA_REG2, gpio_data_reg2);
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ }
}
EXPORT_SYMBOL(rdc_gpio_set_value);

+/* configure GPIO pin as input */
int rdc_gpio_direction_input(unsigned gpio)
{
+ if (!rdc321x_is_gpio(gpio))
+ return -EINVAL;
+
+ rdc321x_configure_gpio(gpio);
+
return 0;
}
EXPORT_SYMBOL(rdc_gpio_direction_input);

+/* configure GPIO pin as output and set value */
int rdc_gpio_direction_output(unsigned gpio, int value)
{
+ if (!rdc321x_is_gpio(gpio))
+ return -EINVAL;
+
+ gpio_set_value(gpio, value);
+ rdc321x_configure_gpio(gpio);
+
return 0;
}
EXPORT_SYMBOL(rdc_gpio_direction_output);
-
-
diff --git a/arch/x86/mach-rdc321x/platform.c b/arch/x86/mach-rdc321x/platform.c
index dda6024..a037041 100644
--- a/arch/x86/mach-rdc321x/platform.c
+++ b/arch/x86/mach-rdc321x/platform.c
@@ -62,6 +62,8 @@ static struct platform_device *rdc321x_devs[] = {

static int __init rdc_board_setup(void)
{
+ rdc321x_gpio_setup();
+
return platform_add_devices(rdc321x_devs, ARRAY_SIZE(rdc321x_devs));
}

diff --git a/include/asm-x86/mach-rdc321x/gpio.h b/include/asm-x86/mach-rdc321x/gpio.h
index db31b92..acce0b7 100644
--- a/include/asm-x86/mach-rdc321x/gpio.h
+++ b/include/asm-x86/mach-rdc321x/gpio.h
@@ -5,19 +5,20 @@ extern int rdc_gpio_get_value(unsigned gpio);
extern void rdc_gpio_set_value(unsigned gpio, int value);
extern int rdc_gpio_direction_input(unsigned gpio);
extern int rdc_gpio_direction_output(unsigned gpio, int value);
-
+extern int rdc_gpio_request(unsigned gpio, const char *label);
+extern void rdc_gpio_free(unsigned gpio);
+extern void __init rdc321x_gpio_setup(void);

/* Wrappers for the arch-neutral GPIO API */

static inline int gpio_request(unsigned gpio, const char *label)
{
- /* Not yet implemented */
- return 0;
+ return rdc_gpio_request(gpio, label);
}

static inline void gpio_free(unsigned gpio)
{
- /* Not yet implemented */
+ rdc_gpio_free(gpio);
}

static inline int gpio_direction_input(unsigned gpio)
diff --git a/include/asm-x86/mach-rdc321x/rdc321x_defs.h b/include/asm-x86/mach-rdc321x/rdc321x_defs.h
index 838ba8f..c8e9c8b 100644
--- a/include/asm-x86/mach-rdc321x/rdc321x_defs.h
+++ b/include/asm-x86/mach-rdc321x/rdc321x_defs.h
@@ -3,4 +3,10 @@
/* General purpose configuration and data registers */
#define RDC3210_CFGREG_ADDR 0x0CF8
#define RDC3210_CFGREG_DATA 0x0CFC
-#define RDC_MAX_GPIO 0x3A
+
+#define RDC321X_GPIO_CTRL_REG1 0x48
+#define RDC321X_GPIO_CTRL_REG2 0x84
+#define RDC321X_GPIO_DATA_REG1 0x4c
+#define RDC321X_GPIO_DATA_REG2 0x88
+
+#define RDC321X_MAX_GPIO 58


2008-03-26 22:15:27

by Ingo Molnar

[permalink] [raw]
Subject: Re: [PATCH] [x86] rdc321x: GPIO routines bugfixes


* Florian Fainelli <[email protected]> wrote:

> Hi Ingo,
>
> This should be in 2.6.25 if possible. Thanks !

thanks, applied.

Ingo