Re: [PATCH 1/2] cs5535-gpio: add AMD CS5535/CS5536 GPIO driver support

From: Tobias MÃller
Date: Thu Jun 11 2009 - 14:53:03 EST


Here's the promised patch. :) I tried to solve all issues I had with
Andres' patch.



From: Tobias Mueller <Tobias_Mueller@xxxxxxxxx>

Added mask to enable/disable some GPIO pins.
Added names for GPIO pins.
Added code on GPIO initialisation to disable output/input aux functions.

Signed-off-by: Tobias Mueller <Tobias_Mueller@xxxxxxxxx>
---
diff --git a/drivers/gpio/cs5535-gpio.c b/drivers/gpio/cs5535-gpio.c
index 5613889..8a0b290 100644
--- a/drivers/gpio/cs5535-gpio.c
+++ b/drivers/gpio/cs5535-gpio.c
@@ -18,6 +18,11 @@

#define DRV_NAME "cs5535-gpio"
#define GPIO_BAR 1
+#define GPIO_DEFAULT_MASK 0x0B003C66
+
+static ulong mask = GPIO_DEFAULT_MASK;
+module_param_named(mask, mask, ulong, 0444);
+MODULE_PARM_DESC(mask, "GPIO channel mask.");

static struct cs5535_gpio_chip {
struct gpio_chip chip;
@@ -102,6 +107,38 @@ EXPORT_SYMBOL_GPL(cs5535_gpio_isset);
* Generic gpio_chip API support.
*/

+static int chip_gpio_request(struct gpio_chip *c, unsigned offset)
+{
+ struct cs5535_gpio_chip *chip = (struct cs5535_gpio_chip *) c;
+ unsigned long flags;
+
+ spin_lock_irqsave(&chip->lock, flags);
+
+ /* check if this pin is available */
+ if ((mask & (1 << offset)) == 0) {
+ printk(KERN_INFO DRV_NAME
+ ": pin %u is not available (check mask)\n", offset);
+ return -EINVAL;
+ }
+
+ /* disable output aux 1 & 2 on this pin */
+ __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_AUX1);
+ __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_AUX2);
+
+ /* disable input aux 1 on this pin */
+ __cs5535_gpio_clear(chip, offset, GPIO_INPUT_AUX1);
+
+ /* disable output */
+ __cs5535_gpio_clear(chip, offset, GPIO_OUTPUT_ENABLE);
+
+ /* enable input */
+ __cs5535_gpio_set(chip, offset, GPIO_INPUT_ENABLE);
+
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
static int chip_gpio_get(struct gpio_chip *chip, unsigned offset)
{
return cs5535_gpio_isset(offset, GPIO_OUTPUT_VAL);
@@ -145,19 +182,34 @@ static int chip_direction_output(struct
gpio_chip *c, unsigned offset, int val)
return 0;
}

+static char *cs5535_gpio_names[] = {
+ "GPIO0", "GPIO1", "GPIO2", "GPIO3",
+ "GPIO4", "GPIO5", "GPIO6", "GPIO7",
+ "GPIO8", "GPIO9", "GPIO10", "GPIO11",
+ "GPIO12", "GPIO13", "GPIO14", "GPIO15",
+ "GPIO16", "GPIO17", "GPIO18", "GPIO19",
+ "GPIO20", "GPIO21", "GPIO22", NULL,
+ "GPIO24", "GPIO25", "GPIO26", "GPIO27",
+ "GPIO28", NULL, NULL, NULL,
+};
+
static struct cs5535_gpio_chip cs5535_gpio_chip = {
.chip = {
.owner = THIS_MODULE,
.label = DRV_NAME,

.base = 0,
- .ngpio = 28,
+ .ngpio = 32,
+ .names = cs5535_gpio_names,
+
+ .request = chip_gpio_request,

.get = chip_gpio_get,
.set = chip_gpio_set,

.direction_input = chip_direction_input,
.direction_output = chip_direction_output,
+
},
};

@@ -165,6 +217,7 @@ static int __init cs5535_gpio_probe(struct pci_dev *pdev,
const struct pci_device_id *pci_id)
{
int err;
+ ulong mask_orig = mask;

/* There are two ways to get the GPIO base address; one is by
* fetching it from MSR_LBAR_GPIO, the other is by reading the
@@ -193,6 +246,18 @@ static int __init cs5535_gpio_probe(struct pci_dev *pdev,
dev_info(&pdev->dev, "allocated PCI BAR #%d: base 0x%llx\n", GPIO_BAR,
(unsigned long long) cs5535_gpio_chip.base);

+ /* mask out reserved pins */
+ mask &= 0x1F7FFFFF;
+
+ /* do not allow pin 28, Power Button, as there's special handling
+ * in the PMC needed. (note 12, p. 48) */
+ mask &= ~(1 << 28);
+
+ if (mask_orig != mask)
+ printk(KERN_INFO DRV_NAME
+ ": mask changed from 0x%08lX to 0x%08lX\n",
+ mask_orig, mask);
+
/* finally, register with the generic GPIO API */
err = gpiochip_add(&cs5535_gpio_chip.chip);
if (err) {
--
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