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Blackfin arch: store labels so we later know who allocated GPIO/Peripheral resources

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Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
This commit is contained in:
Michael Hennerich 2007-10-10 22:55:30 +08:00 committed by Bryan Wu
parent b2d1583f8e
commit 40d63406a0
2 changed files with 72 additions and 20 deletions
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87
arch/blackfin/mach-bf548/gpio.c
View file

@ -49,6 +49,9 @@ static struct gpio_port_t *gpio_array[gpio_bank(MAX_BLACKFIN_GPIOS)] = {
static unsigned short reserved_gpio_map[gpio_bank(MAX_BLACKFIN_GPIOS)];
static unsigned short reserved_peri_map[gpio_bank(MAX_BLACKFIN_GPIOS)];
char *str_ident = NULL;
#define RESOURCE_LABEL_SIZE 16
inline int check_gpio(unsigned short gpio)
{
@ -70,7 +73,6 @@ inline void portmux_setup(unsigned short portno, unsigned short function)
pmux |= (function & 0x3) << (2 * gpio_sub_n(portno));
gpio_array[gpio_bank(portno)]->port_mux = pmux;
}
inline u16 get_portmux(unsigned short portno)
@ -80,16 +82,11 @@ inline u16 get_portmux(unsigned short portno)
pmux = gpio_array[gpio_bank(portno)]->port_mux;
return (pmux >> (2 * gpio_sub_n(portno)) & 0x3);
}
static void port_setup(unsigned short gpio, unsigned short usage)
{
if (usage == GPIO_USAGE) {
if (gpio_array[gpio_bank(gpio)]->port_fer & gpio_bit(gpio))
printk(KERN_WARNING
"bfin-gpio: Possible Conflict with Peripheral "
"usage and GPIO %d detected!\n", gpio);
gpio_array[gpio_bank(gpio)]->port_fer &= ~gpio_bit(gpio);
} else
gpio_array[gpio_bank(gpio)]->port_fer |= gpio_bit(gpio);
@ -98,6 +95,11 @@ static void port_setup(unsigned short gpio, unsigned short usage)
static int __init bfin_gpio_init(void)
{
str_ident = kzalloc(RESOURCE_LABEL_SIZE * 256, GFP_KERNEL);
if (!str_ident)
return -ENOMEM;
printk(KERN_INFO "Blackfin GPIO Controller\n");
return 0;
@ -105,11 +107,47 @@ static int __init bfin_gpio_init(void)
arch_initcall(bfin_gpio_init);
static void set_label(unsigned short ident, const char *label)
{
if (label && str_ident) {
strncpy(str_ident + ident * RESOURCE_LABEL_SIZE, label,
RESOURCE_LABEL_SIZE);
str_ident[ident * RESOURCE_LABEL_SIZE +
RESOURCE_LABEL_SIZE - 1] = 0;
}
}
static char *get_label(unsigned short ident)
{
if (!str_ident)
return "UNKNOWN";
return (str_ident[ident * RESOURCE_LABEL_SIZE] ?
(str_ident + ident * RESOURCE_LABEL_SIZE) : "UNKNOWN");
}
static int cmp_label(unsigned short ident, const char *label)
{
if (label && str_ident)
return strncmp(str_ident + ident * RESOURCE_LABEL_SIZE,
label, strlen(label));
else
return -EINVAL;
}
int peripheral_request(unsigned short per, const char *label)
{
unsigned long flags;
unsigned short ident = P_IDENT(per);
/*
* Don't cares are pins with only one dedicated function
*/
if (per & P_DONTCARE)
return 0;
if (!(per & P_DEFINED))
return -ENODEV;
@ -120,8 +158,8 @@ int peripheral_request(unsigned short per, const char *label)
if (unlikely(reserved_gpio_map[gpio_bank(ident)] & gpio_bit(ident))) {
printk(KERN_ERR
"%s: Peripheral %d is already reserved as GPIO!\n",
__FUNCTION__, per);
"%s: Peripheral %d is already reserved as GPIO by %s !\n",
__FUNCTION__, ident, get_label(ident));
dump_stack();
local_irq_restore(flags);
return -EBUSY;
@ -131,22 +169,38 @@ int peripheral_request(unsigned short per, const char *label)
u16 funct = get_portmux(ident);
/*
* Pin functions like AMC address strobes my
* be requested and used by several drivers
*/
if (!((per & P_MAYSHARE) && (funct == P_FUNCT2MUX(per)))) {
/*
* Allow that the identical pin function can
* be requested from the same driver twice
*/
if (cmp_label(ident, label) == 0)
goto anyway;
printk(KERN_ERR
"%s: Peripheral %d is already reserved!\n",
__FUNCTION__, per);
"%s: Peripheral %d function %d is already reserved by %s !\n",
__FUNCTION__, ident, P_FUNCT2MUX(per), get_label(ident));
dump_stack();
local_irq_restore(flags);
return -EBUSY;
}
}
anyway:
reserved_peri_map[gpio_bank(ident)] |= gpio_bit(ident);
portmux_setup(ident, P_FUNCT2MUX(per));
port_setup(ident, PERIPHERAL_USAGE);
local_irq_restore(flags);
set_label(ident, label);
return 0;
}
@ -154,7 +208,6 @@ EXPORT_SYMBOL(peripheral_request);
int peripheral_request_list(unsigned short per[], const char *label)
{
u16 cnt;
int ret;
@ -173,6 +226,9 @@ void peripheral_free(unsigned short per)
unsigned long flags;
unsigned short ident = P_IDENT(per);
if (per & P_DONTCARE)
return;
if (!(per & P_DEFINED))
return;
@ -182,8 +238,6 @@ void peripheral_free(unsigned short per)
local_irq_save(flags);
if (unlikely(!(reserved_peri_map[gpio_bank(ident)] & gpio_bit(ident)))) {
printk(KERN_ERR "bfin-gpio: Peripheral %d wasn't reserved!\n", per);
dump_stack();
local_irq_restore(flags);
return;
}
@ -234,7 +288,8 @@ int gpio_request(unsigned short gpio, const char *label)
local_irq_save(flags);
if (unlikely(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio))) {
printk(KERN_ERR "bfin-gpio: GPIO %d is already reserved!\n", gpio);
printk(KERN_ERR "bfin-gpio: GPIO %d is already reserved by %s !\n",
gpio, get_label(gpio));
dump_stack();
local_irq_restore(flags);
return -EBUSY;
@ -242,7 +297,8 @@ int gpio_request(unsigned short gpio, const char *label)
if (unlikely(reserved_peri_map[gpio_bank(gpio)] & gpio_bit(gpio))) {
printk(KERN_ERR
"bfin-gpio: GPIO %d is already reserved as Peripheral!\n", gpio);
"bfin-gpio: GPIO %d is already reserved as Peripheral by %s !\n",
gpio, get_label(gpio));
dump_stack();
local_irq_restore(flags);
return -EBUSY;
@ -253,6 +309,7 @@ int gpio_request(unsigned short gpio, const char *label)
local_irq_restore(flags);
port_setup(gpio, GPIO_USAGE);
set_label(gpio, label);
return 0;
}

5
include/asm-blackfin/mach-bf548/gpio.h
View file

@ -209,8 +209,3 @@ struct gpio_port_t {
unsigned short dummy7;
unsigned int port_mux;
};
int gpio_request(unsigned short gpio, const char *label);
void peripheral_free(unsigned short per);
int peripheral_request_list(unsigned short per[], const char *label);
void peripheral_free_list(unsigned short per[]);