android_kernel_samsung_msm8976/arch/arm/mach-sa1100/generic.c
David Brownell 28735a7253 [PATCH] gpio_direction_output() needs an initial value
It's been pointed out that output GPIOs should have an initial value, to
avoid signal glitching ...  among other things, it can be some time before
a driver is ready.  This patch corrects that oversight, fixing

 - documentation
 - platforms supporting the GPIO interface
 - users of that call (just one for now, others are pending)

There's only one user of this call for now since most platforms are still
using non-generic GPIO setup code, which in most cases already couples the
initial value with its "set output mode" request.

Note that most platforms are clear about the hardware letting the output
value be set before the pin direction is changed, but the s3c241x docs are
vague on that topic ...  so those chips might not avoid the glitches.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Andrew Victor <andrew@sanpeople.com>
Acked-by: Milan Svoboda <msvoboda@ra.rockwell.com>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-16 19:25:04 -07:00

487 lines
10 KiB
C

/*
* linux/arch/arm/mach-sa1100/generic.c
*
* Author: Nicolas Pitre
*
* Code common to all SA11x0 machines.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/cpufreq.h>
#include <linux/ioport.h>
#include <linux/sched.h> /* just for sched_clock() - funny that */
#include <linux/platform_device.h>
#include <asm/div64.h>
#include <asm/cnt32_to_63.h>
#include <asm/hardware.h>
#include <asm/system.h>
#include <asm/pgtable.h>
#include <asm/mach/map.h>
#include <asm/mach/flash.h>
#include <asm/irq.h>
#include "generic.h"
#define NR_FREQS 16
/*
* This table is setup for a 3.6864MHz Crystal.
*/
static const unsigned short cclk_frequency_100khz[NR_FREQS] = {
590, /* 59.0 MHz */
737, /* 73.7 MHz */
885, /* 88.5 MHz */
1032, /* 103.2 MHz */
1180, /* 118.0 MHz */
1327, /* 132.7 MHz */
1475, /* 147.5 MHz */
1622, /* 162.2 MHz */
1769, /* 176.9 MHz */
1917, /* 191.7 MHz */
2064, /* 206.4 MHz */
2212, /* 221.2 MHz */
2359, /* 235.9 MHz */
2507, /* 250.7 MHz */
2654, /* 265.4 MHz */
2802 /* 280.2 MHz */
};
#if defined(CONFIG_CPU_FREQ_SA1100) || defined(CONFIG_CPU_FREQ_SA1110)
/* rounds up(!) */
unsigned int sa11x0_freq_to_ppcr(unsigned int khz)
{
int i;
khz /= 100;
for (i = 0; i < NR_FREQS; i++)
if (cclk_frequency_100khz[i] >= khz)
break;
return i;
}
unsigned int sa11x0_ppcr_to_freq(unsigned int idx)
{
unsigned int freq = 0;
if (idx < NR_FREQS)
freq = cclk_frequency_100khz[idx] * 100;
return freq;
}
/* make sure that only the "userspace" governor is run -- anything else wouldn't make sense on
* this platform, anyway.
*/
int sa11x0_verify_speed(struct cpufreq_policy *policy)
{
unsigned int tmp;
if (policy->cpu)
return -EINVAL;
cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
/* make sure that at least one frequency is within the policy */
tmp = cclk_frequency_100khz[sa11x0_freq_to_ppcr(policy->min)] * 100;
if (tmp > policy->max)
policy->max = tmp;
cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
return 0;
}
unsigned int sa11x0_getspeed(unsigned int cpu)
{
if (cpu)
return 0;
return cclk_frequency_100khz[PPCR & 0xf] * 100;
}
#else
/*
* We still need to provide this so building without cpufreq works.
*/
unsigned int cpufreq_get(unsigned int cpu)
{
return cclk_frequency_100khz[PPCR & 0xf] * 100;
}
EXPORT_SYMBOL(cpufreq_get);
#endif
/*
* This is the SA11x0 sched_clock implementation. This has
* a resolution of 271ns, and a maximum value of 32025597s (370 days).
*
* The return value is guaranteed to be monotonic in that range as
* long as there is always less than 582 seconds between successive
* calls to this function.
*
* ( * 1E9 / 3686400 => * 78125 / 288)
*/
unsigned long long sched_clock(void)
{
unsigned long long v = cnt32_to_63(OSCR);
/* the <<1 gets rid of the cnt_32_to_63 top bit saving on a bic insn */
v *= 78125<<1;
do_div(v, 288<<1);
return v;
}
int gpio_direction_input(unsigned gpio)
{
unsigned long flags;
if (gpio > GPIO_MAX)
return -EINVAL;
local_irq_save(flags);
GPDR &= ~GPIO_GPIO(gpio);
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL(gpio_direction_input);
int gpio_direction_output(unsigned gpio, int value)
{
unsigned long flags;
if (gpio > GPIO_MAX)
return -EINVAL;
local_irq_save(flags);
gpio_set_value(gpio, value);
GPDR |= GPIO_GPIO(gpio);
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL(gpio_direction_output);
/*
* Default power-off for SA1100
*/
static void sa1100_power_off(void)
{
mdelay(100);
local_irq_disable();
/* disable internal oscillator, float CS lines */
PCFR = (PCFR_OPDE | PCFR_FP | PCFR_FS);
/* enable wake-up on GPIO0 (Assabet...) */
PWER = GFER = GRER = 1;
/*
* set scratchpad to zero, just in case it is used as a
* restart address by the bootloader.
*/
PSPR = 0;
/* enter sleep mode */
PMCR = PMCR_SF;
}
static struct resource sa11x0udc_resources[] = {
[0] = {
.start = 0x80000000,
.end = 0x8000ffff,
.flags = IORESOURCE_MEM,
},
};
static u64 sa11x0udc_dma_mask = 0xffffffffUL;
static struct platform_device sa11x0udc_device = {
.name = "sa11x0-udc",
.id = -1,
.dev = {
.dma_mask = &sa11x0udc_dma_mask,
.coherent_dma_mask = 0xffffffff,
},
.num_resources = ARRAY_SIZE(sa11x0udc_resources),
.resource = sa11x0udc_resources,
};
static struct resource sa11x0uart1_resources[] = {
[0] = {
.start = 0x80010000,
.end = 0x8001ffff,
.flags = IORESOURCE_MEM,
},
};
static struct platform_device sa11x0uart1_device = {
.name = "sa11x0-uart",
.id = 1,
.num_resources = ARRAY_SIZE(sa11x0uart1_resources),
.resource = sa11x0uart1_resources,
};
static struct resource sa11x0uart3_resources[] = {
[0] = {
.start = 0x80050000,
.end = 0x8005ffff,
.flags = IORESOURCE_MEM,
},
};
static struct platform_device sa11x0uart3_device = {
.name = "sa11x0-uart",
.id = 3,
.num_resources = ARRAY_SIZE(sa11x0uart3_resources),
.resource = sa11x0uart3_resources,
};
static struct resource sa11x0mcp_resources[] = {
[0] = {
.start = 0x80060000,
.end = 0x8006ffff,
.flags = IORESOURCE_MEM,
},
};
static u64 sa11x0mcp_dma_mask = 0xffffffffUL;
static struct platform_device sa11x0mcp_device = {
.name = "sa11x0-mcp",
.id = -1,
.dev = {
.dma_mask = &sa11x0mcp_dma_mask,
.coherent_dma_mask = 0xffffffff,
},
.num_resources = ARRAY_SIZE(sa11x0mcp_resources),
.resource = sa11x0mcp_resources,
};
void sa11x0_set_mcp_data(struct mcp_plat_data *data)
{
sa11x0mcp_device.dev.platform_data = data;
}
static struct resource sa11x0ssp_resources[] = {
[0] = {
.start = 0x80070000,
.end = 0x8007ffff,
.flags = IORESOURCE_MEM,
},
};
static u64 sa11x0ssp_dma_mask = 0xffffffffUL;
static struct platform_device sa11x0ssp_device = {
.name = "sa11x0-ssp",
.id = -1,
.dev = {
.dma_mask = &sa11x0ssp_dma_mask,
.coherent_dma_mask = 0xffffffff,
},
.num_resources = ARRAY_SIZE(sa11x0ssp_resources),
.resource = sa11x0ssp_resources,
};
static struct resource sa11x0fb_resources[] = {
[0] = {
.start = 0xb0100000,
.end = 0xb010ffff,
.flags = IORESOURCE_MEM,
},
[1] = {
.start = IRQ_LCD,
.end = IRQ_LCD,
.flags = IORESOURCE_IRQ,
},
};
static struct platform_device sa11x0fb_device = {
.name = "sa11x0-fb",
.id = -1,
.dev = {
.coherent_dma_mask = 0xffffffff,
},
.num_resources = ARRAY_SIZE(sa11x0fb_resources),
.resource = sa11x0fb_resources,
};
static struct platform_device sa11x0pcmcia_device = {
.name = "sa11x0-pcmcia",
.id = -1,
};
static struct platform_device sa11x0mtd_device = {
.name = "flash",
.id = -1,
};
void sa11x0_set_flash_data(struct flash_platform_data *flash,
struct resource *res, int nr)
{
flash->name = "sa1100";
sa11x0mtd_device.dev.platform_data = flash;
sa11x0mtd_device.resource = res;
sa11x0mtd_device.num_resources = nr;
}
static struct resource sa11x0ir_resources[] = {
{
.start = __PREG(Ser2UTCR0),
.end = __PREG(Ser2UTCR0) + 0x24 - 1,
.flags = IORESOURCE_MEM,
}, {
.start = __PREG(Ser2HSCR0),
.end = __PREG(Ser2HSCR0) + 0x1c - 1,
.flags = IORESOURCE_MEM,
}, {
.start = __PREG(Ser2HSCR2),
.end = __PREG(Ser2HSCR2) + 0x04 - 1,
.flags = IORESOURCE_MEM,
}, {
.start = IRQ_Ser2ICP,
.end = IRQ_Ser2ICP,
.flags = IORESOURCE_IRQ,
}
};
static struct platform_device sa11x0ir_device = {
.name = "sa11x0-ir",
.id = -1,
.num_resources = ARRAY_SIZE(sa11x0ir_resources),
.resource = sa11x0ir_resources,
};
void sa11x0_set_irda_data(struct irda_platform_data *irda)
{
sa11x0ir_device.dev.platform_data = irda;
}
static struct platform_device sa11x0rtc_device = {
.name = "sa1100-rtc",
.id = -1,
};
static struct platform_device *sa11x0_devices[] __initdata = {
&sa11x0udc_device,
&sa11x0uart1_device,
&sa11x0uart3_device,
&sa11x0mcp_device,
&sa11x0ssp_device,
&sa11x0pcmcia_device,
&sa11x0fb_device,
&sa11x0mtd_device,
&sa11x0rtc_device,
};
static int __init sa1100_init(void)
{
pm_power_off = sa1100_power_off;
if (sa11x0ir_device.dev.platform_data)
platform_device_register(&sa11x0ir_device);
return platform_add_devices(sa11x0_devices, ARRAY_SIZE(sa11x0_devices));
}
arch_initcall(sa1100_init);
void (*sa1100fb_backlight_power)(int on);
void (*sa1100fb_lcd_power)(int on);
EXPORT_SYMBOL(sa1100fb_backlight_power);
EXPORT_SYMBOL(sa1100fb_lcd_power);
/*
* Common I/O mapping:
*
* Typically, static virtual address mappings are as follow:
*
* 0xf0000000-0xf3ffffff: miscellaneous stuff (CPLDs, etc.)
* 0xf4000000-0xf4ffffff: SA-1111
* 0xf5000000-0xf5ffffff: reserved (used by cache flushing area)
* 0xf6000000-0xfffeffff: reserved (internal SA1100 IO defined above)
* 0xffff0000-0xffff0fff: SA1100 exception vectors
* 0xffff2000-0xffff2fff: Minicache copy_user_page area
*
* Below 0xe8000000 is reserved for vm allocation.
*
* The machine specific code must provide the extra mapping beside the
* default mapping provided here.
*/
static struct map_desc standard_io_desc[] __initdata = {
{ /* PCM */
.virtual = 0xf8000000,
.pfn = __phys_to_pfn(0x80000000),
.length = 0x00100000,
.type = MT_DEVICE
}, { /* SCM */
.virtual = 0xfa000000,
.pfn = __phys_to_pfn(0x90000000),
.length = 0x00100000,
.type = MT_DEVICE
}, { /* MER */
.virtual = 0xfc000000,
.pfn = __phys_to_pfn(0xa0000000),
.length = 0x00100000,
.type = MT_DEVICE
}, { /* LCD + DMA */
.virtual = 0xfe000000,
.pfn = __phys_to_pfn(0xb0000000),
.length = 0x00200000,
.type = MT_DEVICE
},
};
void __init sa1100_map_io(void)
{
iotable_init(standard_io_desc, ARRAY_SIZE(standard_io_desc));
}
/*
* Disable the memory bus request/grant signals on the SA1110 to
* ensure that we don't receive spurious memory requests. We set
* the MBGNT signal false to ensure the SA1111 doesn't own the
* SDRAM bus.
*/
void __init sa1110_mb_disable(void)
{
unsigned long flags;
local_irq_save(flags);
PGSR &= ~GPIO_MBGNT;
GPCR = GPIO_MBGNT;
GPDR = (GPDR & ~GPIO_MBREQ) | GPIO_MBGNT;
GAFR &= ~(GPIO_MBGNT | GPIO_MBREQ);
local_irq_restore(flags);
}
/*
* If the system is going to use the SA-1111 DMA engines, set up
* the memory bus request/grant pins.
*/
void __init sa1110_mb_enable(void)
{
unsigned long flags;
local_irq_save(flags);
PGSR &= ~GPIO_MBGNT;
GPCR = GPIO_MBGNT;
GPDR = (GPDR & ~GPIO_MBREQ) | GPIO_MBGNT;
GAFR |= (GPIO_MBGNT | GPIO_MBREQ);
TUCR |= TUCR_MR;
local_irq_restore(flags);
}