diff options
Diffstat (limited to 'arch/ppc64/kernel/pmac_low_i2c.c')
| -rw-r--r-- | arch/ppc64/kernel/pmac_low_i2c.c | 523 |
1 files changed, 0 insertions, 523 deletions
diff --git a/arch/ppc64/kernel/pmac_low_i2c.c b/arch/ppc64/kernel/pmac_low_i2c.c deleted file mode 100644 index f3f39e8e337..00000000000 --- a/arch/ppc64/kernel/pmac_low_i2c.c +++ /dev/null @@ -1,523 +0,0 @@ -/* - * arch/ppc/platforms/pmac_low_i2c.c - * - * Copyright (C) 2003 Ben. Herrenschmidt (benh@kernel.crashing.org) - * - * 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 file contains some low-level i2c access routines that - * need to be used by various bits of the PowerMac platform code - * at times where the real asynchronous & interrupt driven driver - * cannot be used. The API borrows some semantics from the darwin - * driver in order to ease the implementation of the platform - * properties parser - */ - -#undef DEBUG - -#include <linux/config.h> -#include <linux/types.h> -#include <linux/sched.h> -#include <linux/init.h> -#include <linux/module.h> -#include <linux/adb.h> -#include <linux/pmu.h> -#include <asm/keylargo.h> -#include <asm/uninorth.h> -#include <asm/io.h> -#include <asm/prom.h> -#include <asm/machdep.h> -#include <asm/pmac_low_i2c.h> - -#define MAX_LOW_I2C_HOST 4 - -#ifdef DEBUG -#define DBG(x...) do {\ - printk(KERN_DEBUG "KW:" x); \ - } while(0) -#else -#define DBG(x...) -#endif - -struct low_i2c_host; - -typedef int (*low_i2c_func_t)(struct low_i2c_host *host, u8 addr, u8 sub, u8 *data, int len); - -struct low_i2c_host -{ - struct device_node *np; /* OF device node */ - struct semaphore mutex; /* Access mutex for use by i2c-keywest */ - low_i2c_func_t func; /* Access function */ - unsigned int is_open : 1; /* Poor man's access control */ - int mode; /* Current mode */ - int channel; /* Current channel */ - int num_channels; /* Number of channels */ - void __iomem *base; /* For keywest-i2c, base address */ - int bsteps; /* And register stepping */ - int speed; /* And speed */ -}; - -static struct low_i2c_host low_i2c_hosts[MAX_LOW_I2C_HOST]; - -/* No locking is necessary on allocation, we are running way before - * anything can race with us - */ -static struct low_i2c_host *find_low_i2c_host(struct device_node *np) -{ - int i; - - for (i = 0; i < MAX_LOW_I2C_HOST; i++) - if (low_i2c_hosts[i].np == np) - return &low_i2c_hosts[i]; - return NULL; -} - -/* - * - * i2c-keywest implementation (UniNorth, U2, U3, Keylargo's) - * - */ - -/* - * Keywest i2c definitions borrowed from drivers/i2c/i2c-keywest.h, - * should be moved somewhere in include/asm-ppc/ - */ -/* Register indices */ -typedef enum { - reg_mode = 0, - reg_control, - reg_status, - reg_isr, - reg_ier, - reg_addr, - reg_subaddr, - reg_data -} reg_t; - - -/* Mode register */ -#define KW_I2C_MODE_100KHZ 0x00 -#define KW_I2C_MODE_50KHZ 0x01 -#define KW_I2C_MODE_25KHZ 0x02 -#define KW_I2C_MODE_DUMB 0x00 -#define KW_I2C_MODE_STANDARD 0x04 -#define KW_I2C_MODE_STANDARDSUB 0x08 -#define KW_I2C_MODE_COMBINED 0x0C -#define KW_I2C_MODE_MODE_MASK 0x0C -#define KW_I2C_MODE_CHAN_MASK 0xF0 - -/* Control register */ -#define KW_I2C_CTL_AAK 0x01 -#define KW_I2C_CTL_XADDR 0x02 -#define KW_I2C_CTL_STOP 0x04 -#define KW_I2C_CTL_START 0x08 - -/* Status register */ -#define KW_I2C_STAT_BUSY 0x01 -#define KW_I2C_STAT_LAST_AAK 0x02 -#define KW_I2C_STAT_LAST_RW 0x04 -#define KW_I2C_STAT_SDA 0x08 -#define KW_I2C_STAT_SCL 0x10 - -/* IER & ISR registers */ -#define KW_I2C_IRQ_DATA 0x01 -#define KW_I2C_IRQ_ADDR 0x02 -#define KW_I2C_IRQ_STOP 0x04 -#define KW_I2C_IRQ_START 0x08 -#define KW_I2C_IRQ_MASK 0x0F - -/* State machine states */ -enum { - state_idle, - state_addr, - state_read, - state_write, - state_stop, - state_dead -}; - -#define WRONG_STATE(name) do {\ - printk(KERN_DEBUG "KW: wrong state. Got %s, state: %s (isr: %02x)\n", \ - name, __kw_state_names[state], isr); \ - } while(0) - -static const char *__kw_state_names[] = { - "state_idle", - "state_addr", - "state_read", - "state_write", - "state_stop", - "state_dead" -}; - -static inline u8 __kw_read_reg(struct low_i2c_host *host, reg_t reg) -{ - return readb(host->base + (((unsigned int)reg) << host->bsteps)); -} - -static inline void __kw_write_reg(struct low_i2c_host *host, reg_t reg, u8 val) -{ - writeb(val, host->base + (((unsigned)reg) << host->bsteps)); - (void)__kw_read_reg(host, reg_subaddr); -} - -#define kw_write_reg(reg, val) __kw_write_reg(host, reg, val) -#define kw_read_reg(reg) __kw_read_reg(host, reg) - - -/* Don't schedule, the g5 fan controller is too - * timing sensitive - */ -static u8 kw_wait_interrupt(struct low_i2c_host* host) -{ - int i, j; - u8 isr; - - for (i = 0; i < 100000; i++) { - isr = kw_read_reg(reg_isr) & KW_I2C_IRQ_MASK; - if (isr != 0) - return isr; - - /* This code is used with the timebase frozen, we cannot rely - * on udelay ! For now, just use a bogus loop - */ - for (j = 1; j < 10000; j++) - mb(); - } - return isr; -} - -static int kw_handle_interrupt(struct low_i2c_host *host, int state, int rw, int *rc, u8 **data, int *len, u8 isr) -{ - u8 ack; - - DBG("kw_handle_interrupt(%s, isr: %x)\n", __kw_state_names[state], isr); - - if (isr == 0) { - if (state != state_stop) { - DBG("KW: Timeout !\n"); - *rc = -EIO; - goto stop; - } - if (state == state_stop) { - ack = kw_read_reg(reg_status); - if (!(ack & KW_I2C_STAT_BUSY)) { - state = state_idle; - kw_write_reg(reg_ier, 0x00); - } - } - return state; - } - - if (isr & KW_I2C_IRQ_ADDR) { - ack = kw_read_reg(reg_status); - if (state != state_addr) { - kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR); - WRONG_STATE("KW_I2C_IRQ_ADDR"); - *rc = -EIO; - goto stop; - } - if ((ack & KW_I2C_STAT_LAST_AAK) == 0) { - *rc = -ENODEV; - DBG("KW: NAK on address\n"); - return state_stop; - } else { - if (rw) { - state = state_read; - if (*len > 1) - kw_write_reg(reg_control, KW_I2C_CTL_AAK); - } else { - state = state_write; - kw_write_reg(reg_data, **data); - (*data)++; (*len)--; - } - } - kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR); - } - - if (isr & KW_I2C_IRQ_DATA) { - if (state == state_read) { - **data = kw_read_reg(reg_data); - (*data)++; (*len)--; - kw_write_reg(reg_isr, KW_I2C_IRQ_DATA); - if ((*len) == 0) - state = state_stop; - else if ((*len) == 1) - kw_write_reg(reg_control, 0); - } else if (state == state_write) { - ack = kw_read_reg(reg_status); - if ((ack & KW_I2C_STAT_LAST_AAK) == 0) { - DBG("KW: nack on data write\n"); - *rc = -EIO; - goto stop; - } else if (*len) { - kw_write_reg(reg_data, **data); - (*data)++; (*len)--; - } else { - kw_write_reg(reg_control, KW_I2C_CTL_STOP); - state = state_stop; - *rc = 0; - } - kw_write_reg(reg_isr, KW_I2C_IRQ_DATA); - } else { - kw_write_reg(reg_isr, KW_I2C_IRQ_DATA); - WRONG_STATE("KW_I2C_IRQ_DATA"); - if (state != state_stop) { - *rc = -EIO; - goto stop; - } - } - } - - if (isr & KW_I2C_IRQ_STOP) { - kw_write_reg(reg_isr, KW_I2C_IRQ_STOP); - if (state != state_stop) { - WRONG_STATE("KW_I2C_IRQ_STOP"); - *rc = -EIO; - } - return state_idle; - } - - if (isr & KW_I2C_IRQ_START) - kw_write_reg(reg_isr, KW_I2C_IRQ_START); - - return state; - - stop: - kw_write_reg(reg_control, KW_I2C_CTL_STOP); - return state_stop; -} - -static int keywest_low_i2c_func(struct low_i2c_host *host, u8 addr, u8 subaddr, u8 *data, int len) -{ - u8 mode_reg = host->speed; - int state = state_addr; - int rc = 0; - - /* Setup mode & subaddress if any */ - switch(host->mode) { - case pmac_low_i2c_mode_dumb: - printk(KERN_ERR "low_i2c: Dumb mode not supported !\n"); - return -EINVAL; - case pmac_low_i2c_mode_std: - mode_reg |= KW_I2C_MODE_STANDARD; - break; - case pmac_low_i2c_mode_stdsub: - mode_reg |= KW_I2C_MODE_STANDARDSUB; - break; - case pmac_low_i2c_mode_combined: - mode_reg |= KW_I2C_MODE_COMBINED; - break; - } - - /* Setup channel & clear pending irqs */ - kw_write_reg(reg_isr, kw_read_reg(reg_isr)); - kw_write_reg(reg_mode, mode_reg | (host->channel << 4)); - kw_write_reg(reg_status, 0); - - /* Set up address and r/w bit */ - kw_write_reg(reg_addr, addr); - - /* Set up the sub address */ - if ((mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB - || (mode_reg & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_COMBINED) - kw_write_reg(reg_subaddr, subaddr); - - /* Start sending address & disable interrupt*/ - kw_write_reg(reg_ier, 0 /*KW_I2C_IRQ_MASK*/); - kw_write_reg(reg_control, KW_I2C_CTL_XADDR); - - /* State machine, to turn into an interrupt handler */ - while(state != state_idle) { - u8 isr = kw_wait_interrupt(host); - state = kw_handle_interrupt(host, state, addr & 1, &rc, &data, &len, isr); - } - - return rc; -} - -static void keywest_low_i2c_add(struct device_node *np) -{ - struct low_i2c_host *host = find_low_i2c_host(NULL); - u32 *psteps, *prate, steps, aoffset = 0; - struct device_node *parent; - - if (host == NULL) { - printk(KERN_ERR "low_i2c: Can't allocate host for %s\n", - np->full_name); - return; - } - memset(host, 0, sizeof(*host)); - - init_MUTEX(&host->mutex); - host->np = of_node_get(np); - psteps = (u32 *)get_property(np, "AAPL,address-step", NULL); - steps = psteps ? (*psteps) : 0x10; - for (host->bsteps = 0; (steps & 0x01) == 0; host->bsteps++) - steps >>= 1; - parent = of_get_parent(np); - host->num_channels = 1; - if (parent && parent->name[0] == 'u') { - host->num_channels = 2; - aoffset = 3; - } - /* Select interface rate */ - host->speed = KW_I2C_MODE_100KHZ; - prate = (u32 *)get_property(np, "AAPL,i2c-rate", NULL); - if (prate) switch(*prate) { - case 100: - host->speed = KW_I2C_MODE_100KHZ; - break; - case 50: - host->speed = KW_I2C_MODE_50KHZ; - break; - case 25: - host->speed = KW_I2C_MODE_25KHZ; - break; - } - - host->mode = pmac_low_i2c_mode_std; - host->base = ioremap(np->addrs[0].address + aoffset, - np->addrs[0].size); - host->func = keywest_low_i2c_func; -} - -/* - * - * PMU implementation - * - */ - - -#ifdef CONFIG_ADB_PMU - -static int pmu_low_i2c_func(struct low_i2c_host *host, u8 addr, u8 sub, u8 *data, int len) -{ - // TODO - return -ENODEV; -} - -static void pmu_low_i2c_add(struct device_node *np) -{ - struct low_i2c_host *host = find_low_i2c_host(NULL); - - if (host == NULL) { - printk(KERN_ERR "low_i2c: Can't allocate host for %s\n", - np->full_name); - return; - } - memset(host, 0, sizeof(*host)); - - init_MUTEX(&host->mutex); - host->np = of_node_get(np); - host->num_channels = 3; - host->mode = pmac_low_i2c_mode_std; - host->func = pmu_low_i2c_func; -} - -#endif /* CONFIG_ADB_PMU */ - -void __init pmac_init_low_i2c(void) -{ - struct device_node *np; - - /* Probe keywest-i2c busses */ - np = of_find_compatible_node(NULL, "i2c", "keywest-i2c"); - while(np) { - keywest_low_i2c_add(np); - np = of_find_compatible_node(np, "i2c", "keywest-i2c"); - } - -#ifdef CONFIG_ADB_PMU - /* Probe PMU busses */ - np = of_find_node_by_name(NULL, "via-pmu"); - if (np) - pmu_low_i2c_add(np); -#endif /* CONFIG_ADB_PMU */ - - /* TODO: Add CUDA support as well */ -} - -int pmac_low_i2c_lock(struct device_node *np) -{ - struct low_i2c_host *host = find_low_i2c_host(np); - - if (!host) - return -ENODEV; - down(&host->mutex); - return 0; -} -EXPORT_SYMBOL(pmac_low_i2c_lock); - -int pmac_low_i2c_unlock(struct device_node *np) -{ - struct low_i2c_host *host = find_low_i2c_host(np); - - if (!host) - return -ENODEV; - up(&host->mutex); - return 0; -} -EXPORT_SYMBOL(pmac_low_i2c_unlock); - - -int pmac_low_i2c_open(struct device_node *np, int channel) -{ - struct low_i2c_host *host = find_low_i2c_host(np); - - if (!host) - return -ENODEV; - - if (channel >= host->num_channels) - return -EINVAL; - - down(&host->mutex); - host->is_open = 1; - host->channel = channel; - - return 0; -} -EXPORT_SYMBOL(pmac_low_i2c_open); - -int pmac_low_i2c_close(struct device_node *np) -{ - struct low_i2c_host *host = find_low_i2c_host(np); - - if (!host) - return -ENODEV; - - host->is_open = 0; - up(&host->mutex); - - return 0; -} -EXPORT_SYMBOL(pmac_low_i2c_close); - -int pmac_low_i2c_setmode(struct device_node *np, int mode) -{ - struct low_i2c_host *host = find_low_i2c_host(np); - - if (!host) - return -ENODEV; - WARN_ON(!host->is_open); - host->mode = mode; - - return 0; -} -EXPORT_SYMBOL(pmac_low_i2c_setmode); - -int pmac_low_i2c_xfer(struct device_node *np, u8 addrdir, u8 subaddr, u8 *data, int len) -{ - struct low_i2c_host *host = find_low_i2c_host(np); - - if (!host) - return -ENODEV; - WARN_ON(!host->is_open); - - return host->func(host, addrdir, subaddr, data, len); -} -EXPORT_SYMBOL(pmac_low_i2c_xfer); - |