diff options
Diffstat (limited to 'arch/powerpc/platforms/powermac/low_i2c.c')
| -rw-r--r-- | arch/powerpc/platforms/powermac/low_i2c.c | 1513 |
1 files changed, 1513 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powermac/low_i2c.c b/arch/powerpc/platforms/powermac/low_i2c.c new file mode 100644 index 000000000..df89d9162 --- /dev/null +++ b/arch/powerpc/platforms/powermac/low_i2c.c @@ -0,0 +1,1513 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * arch/powerpc/platforms/powermac/low_i2c.c + * + * Copyright (C) 2003-2005 Ben. Herrenschmidt (benh@kernel.crashing.org) + * + * The linux i2c layer isn't completely suitable for our needs for various + * reasons ranging from too late initialisation to semantics not perfectly + * matching some requirements of the apple platform functions etc... + * + * This file thus provides a simple low level unified i2c interface for + * powermac that covers the various types of i2c busses used in Apple machines. + * For now, keywest, PMU and SMU, though we could add Cuda, or other bit + * banging busses found on older chipsets in earlier machines if we ever need + * one of them. + * + * The drivers in this file are synchronous/blocking. In addition, the + * keywest one is fairly slow due to the use of msleep instead of interrupts + * as the interrupt is currently used by i2c-keywest. In the long run, we + * might want to get rid of those high-level interfaces to linux i2c layer + * either completely (converting all drivers) or replacing them all with a + * single stub driver on top of this one. Once done, the interrupt will be + * available for our use. + */ + +#undef DEBUG +#undef DEBUG_LOW + +#include <linux/types.h> +#include <linux/sched.h> +#include <linux/init.h> +#include <linux/export.h> +#include <linux/adb.h> +#include <linux/pmu.h> +#include <linux/delay.h> +#include <linux/completion.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/timer.h> +#include <linux/mutex.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#include <asm/keylargo.h> +#include <asm/uninorth.h> +#include <asm/io.h> +#include <asm/prom.h> +#include <asm/machdep.h> +#include <asm/smu.h> +#include <asm/pmac_pfunc.h> +#include <asm/pmac_low_i2c.h> + +#ifdef DEBUG +#define DBG(x...) do {\ + printk(KERN_DEBUG "low_i2c:" x); \ + } while(0) +#else +#define DBG(x...) +#endif + +#ifdef DEBUG_LOW +#define DBG_LOW(x...) do {\ + printk(KERN_DEBUG "low_i2c:" x); \ + } while(0) +#else +#define DBG_LOW(x...) +#endif + + +static int pmac_i2c_force_poll = 1; + +/* + * A bus structure. Each bus in the system has such a structure associated. + */ +struct pmac_i2c_bus +{ + struct list_head link; + struct device_node *controller; + struct device_node *busnode; + int type; + int flags; + struct i2c_adapter adapter; + void *hostdata; + int channel; /* some hosts have multiple */ + int mode; /* current mode */ + struct mutex mutex; + int opened; + int polled; /* open mode */ + struct platform_device *platform_dev; + struct lock_class_key lock_key; + + /* ops */ + int (*open)(struct pmac_i2c_bus *bus); + void (*close)(struct pmac_i2c_bus *bus); + int (*xfer)(struct pmac_i2c_bus *bus, u8 addrdir, int subsize, + u32 subaddr, u8 *data, int len); +}; + +static LIST_HEAD(pmac_i2c_busses); + +/* + * Keywest implementation + */ + +struct pmac_i2c_host_kw +{ + struct mutex mutex; /* Access mutex for use by + * i2c-keywest */ + void __iomem *base; /* register base address */ + int bsteps; /* register stepping */ + int speed; /* speed */ + int irq; + u8 *data; + unsigned len; + int state; + int rw; + int polled; + int result; + struct completion complete; + spinlock_t lock; + struct timer_list timeout_timer; +}; + +/* Register indices */ +typedef enum { + reg_mode = 0, + reg_control, + reg_status, + reg_isr, + reg_ier, + reg_addr, + reg_subaddr, + reg_data +} reg_t; + +/* The Tumbler audio equalizer can be really slow sometimes */ +#define KW_POLL_TIMEOUT (2*HZ) + +/* 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[host->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 pmac_i2c_host_kw *host, reg_t reg) +{ + return readb(host->base + (((unsigned int)reg) << host->bsteps)); +} + +static inline void __kw_write_reg(struct pmac_i2c_host_kw *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) + +static u8 kw_i2c_wait_interrupt(struct pmac_i2c_host_kw *host) +{ + int i, j; + u8 isr; + + for (i = 0; i < 1000; 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 nor schedule when in polled mode ! + * For now, just use a bogus loop.... + */ + if (host->polled) { + for (j = 1; j < 100000; j++) + mb(); + } else + msleep(1); + } + return isr; +} + +static void kw_i2c_do_stop(struct pmac_i2c_host_kw *host, int result) +{ + kw_write_reg(reg_control, KW_I2C_CTL_STOP); + host->state = state_stop; + host->result = result; +} + + +static void kw_i2c_handle_interrupt(struct pmac_i2c_host_kw *host, u8 isr) +{ + u8 ack; + + DBG_LOW("kw_handle_interrupt(%s, isr: %x)\n", + __kw_state_names[host->state], isr); + + if (host->state == state_idle) { + printk(KERN_WARNING "low_i2c: Keywest got an out of state" + " interrupt, ignoring\n"); + kw_write_reg(reg_isr, isr); + return; + } + + if (isr == 0) { + printk(KERN_WARNING "low_i2c: Timeout in i2c transfer" + " on keywest !\n"); + if (host->state != state_stop) { + kw_i2c_do_stop(host, -EIO); + return; + } + ack = kw_read_reg(reg_status); + if (ack & KW_I2C_STAT_BUSY) + kw_write_reg(reg_status, 0); + host->state = state_idle; + kw_write_reg(reg_ier, 0x00); + if (!host->polled) + complete(&host->complete); + return; + } + + if (isr & KW_I2C_IRQ_ADDR) { + ack = kw_read_reg(reg_status); + if (host->state != state_addr) { + WRONG_STATE("KW_I2C_IRQ_ADDR"); + kw_i2c_do_stop(host, -EIO); + } + if ((ack & KW_I2C_STAT_LAST_AAK) == 0) { + host->result = -ENXIO; + host->state = state_stop; + DBG_LOW("KW: NAK on address\n"); + } else { + if (host->len == 0) + kw_i2c_do_stop(host, 0); + else if (host->rw) { + host->state = state_read; + if (host->len > 1) + kw_write_reg(reg_control, + KW_I2C_CTL_AAK); + } else { + host->state = state_write; + kw_write_reg(reg_data, *(host->data++)); + host->len--; + } + } + kw_write_reg(reg_isr, KW_I2C_IRQ_ADDR); + } + + if (isr & KW_I2C_IRQ_DATA) { + if (host->state == state_read) { + *(host->data++) = kw_read_reg(reg_data); + host->len--; + kw_write_reg(reg_isr, KW_I2C_IRQ_DATA); + if (host->len == 0) + host->state = state_stop; + else if (host->len == 1) + kw_write_reg(reg_control, 0); + } else if (host->state == state_write) { + ack = kw_read_reg(reg_status); + if ((ack & KW_I2C_STAT_LAST_AAK) == 0) { + DBG_LOW("KW: nack on data write\n"); + host->result = -EFBIG; + host->state = state_stop; + } else if (host->len) { + kw_write_reg(reg_data, *(host->data++)); + host->len--; + } else + kw_i2c_do_stop(host, 0); + } else { + WRONG_STATE("KW_I2C_IRQ_DATA"); + if (host->state != state_stop) + kw_i2c_do_stop(host, -EIO); + } + kw_write_reg(reg_isr, KW_I2C_IRQ_DATA); + } + + if (isr & KW_I2C_IRQ_STOP) { + kw_write_reg(reg_isr, KW_I2C_IRQ_STOP); + if (host->state != state_stop) { + WRONG_STATE("KW_I2C_IRQ_STOP"); + host->result = -EIO; + } + host->state = state_idle; + if (!host->polled) + complete(&host->complete); + } + + /* Below should only happen in manual mode which we don't use ... */ + if (isr & KW_I2C_IRQ_START) + kw_write_reg(reg_isr, KW_I2C_IRQ_START); + +} + +/* Interrupt handler */ +static irqreturn_t kw_i2c_irq(int irq, void *dev_id) +{ + struct pmac_i2c_host_kw *host = dev_id; + unsigned long flags; + + spin_lock_irqsave(&host->lock, flags); + del_timer(&host->timeout_timer); + kw_i2c_handle_interrupt(host, kw_read_reg(reg_isr)); + if (host->state != state_idle) { + host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT; + add_timer(&host->timeout_timer); + } + spin_unlock_irqrestore(&host->lock, flags); + return IRQ_HANDLED; +} + +static void kw_i2c_timeout(struct timer_list *t) +{ + struct pmac_i2c_host_kw *host = from_timer(host, t, timeout_timer); + unsigned long flags; + + spin_lock_irqsave(&host->lock, flags); + + /* + * If the timer is pending, that means we raced with the + * irq, in which case we just return + */ + if (timer_pending(&host->timeout_timer)) + goto skip; + + kw_i2c_handle_interrupt(host, kw_read_reg(reg_isr)); + if (host->state != state_idle) { + host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT; + add_timer(&host->timeout_timer); + } + skip: + spin_unlock_irqrestore(&host->lock, flags); +} + +static int kw_i2c_open(struct pmac_i2c_bus *bus) +{ + struct pmac_i2c_host_kw *host = bus->hostdata; + mutex_lock(&host->mutex); + return 0; +} + +static void kw_i2c_close(struct pmac_i2c_bus *bus) +{ + struct pmac_i2c_host_kw *host = bus->hostdata; + mutex_unlock(&host->mutex); +} + +static int kw_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize, + u32 subaddr, u8 *data, int len) +{ + struct pmac_i2c_host_kw *host = bus->hostdata; + u8 mode_reg = host->speed; + int use_irq = host->irq && !bus->polled; + + /* Setup mode & subaddress if any */ + switch(bus->mode) { + case pmac_i2c_mode_dumb: + return -EINVAL; + case pmac_i2c_mode_std: + mode_reg |= KW_I2C_MODE_STANDARD; + if (subsize != 0) + return -EINVAL; + break; + case pmac_i2c_mode_stdsub: + mode_reg |= KW_I2C_MODE_STANDARDSUB; + if (subsize != 1) + return -EINVAL; + break; + case pmac_i2c_mode_combined: + mode_reg |= KW_I2C_MODE_COMBINED; + if (subsize != 1) + return -EINVAL; + break; + } + + /* Setup channel & clear pending irqs */ + kw_write_reg(reg_isr, kw_read_reg(reg_isr)); + kw_write_reg(reg_mode, mode_reg | (bus->channel << 4)); + kw_write_reg(reg_status, 0); + + /* Set up address and r/w bit, strip possible stale bus number from + * address top bits + */ + kw_write_reg(reg_addr, addrdir & 0xff); + + /* 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); + + /* Prepare for async operations */ + host->data = data; + host->len = len; + host->state = state_addr; + host->result = 0; + host->rw = (addrdir & 1); + host->polled = bus->polled; + + /* Enable interrupt if not using polled mode and interrupt is + * available + */ + if (use_irq) { + /* Clear completion */ + reinit_completion(&host->complete); + /* Ack stale interrupts */ + kw_write_reg(reg_isr, kw_read_reg(reg_isr)); + /* Arm timeout */ + host->timeout_timer.expires = jiffies + KW_POLL_TIMEOUT; + add_timer(&host->timeout_timer); + /* Enable emission */ + kw_write_reg(reg_ier, KW_I2C_IRQ_MASK); + } + + /* Start sending address */ + kw_write_reg(reg_control, KW_I2C_CTL_XADDR); + + /* Wait for completion */ + if (use_irq) + wait_for_completion(&host->complete); + else { + while(host->state != state_idle) { + unsigned long flags; + + u8 isr = kw_i2c_wait_interrupt(host); + spin_lock_irqsave(&host->lock, flags); + kw_i2c_handle_interrupt(host, isr); + spin_unlock_irqrestore(&host->lock, flags); + } + } + + /* Disable emission */ + kw_write_reg(reg_ier, 0); + + return host->result; +} + +static struct pmac_i2c_host_kw *__init kw_i2c_host_init(struct device_node *np) +{ + struct pmac_i2c_host_kw *host; + const u32 *psteps, *prate, *addrp; + u32 steps; + + host = kzalloc(sizeof(*host), GFP_KERNEL); + if (host == NULL) { + printk(KERN_ERR "low_i2c: Can't allocate host for %pOF\n", + np); + return NULL; + } + + /* Apple is kind enough to provide a valid AAPL,address property + * on all i2c keywest nodes so far ... we would have to fallback + * to macio parsing if that wasn't the case + */ + addrp = of_get_property(np, "AAPL,address", NULL); + if (addrp == NULL) { + printk(KERN_ERR "low_i2c: Can't find address for %pOF\n", + np); + kfree(host); + return NULL; + } + mutex_init(&host->mutex); + init_completion(&host->complete); + spin_lock_init(&host->lock); + timer_setup(&host->timeout_timer, kw_i2c_timeout, 0); + + psteps = of_get_property(np, "AAPL,address-step", NULL); + steps = psteps ? (*psteps) : 0x10; + for (host->bsteps = 0; (steps & 0x01) == 0; host->bsteps++) + steps >>= 1; + /* Select interface rate */ + host->speed = KW_I2C_MODE_25KHZ; + prate = of_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->irq = irq_of_parse_and_map(np, 0); + if (!host->irq) + printk(KERN_WARNING + "low_i2c: Failed to map interrupt for %pOF\n", + np); + + host->base = ioremap((*addrp), 0x1000); + if (host->base == NULL) { + printk(KERN_ERR "low_i2c: Can't map registers for %pOF\n", + np); + kfree(host); + return NULL; + } + + /* Make sure IRQ is disabled */ + kw_write_reg(reg_ier, 0); + + /* Request chip interrupt. We set IRQF_NO_SUSPEND because we don't + * want that interrupt disabled between the 2 passes of driver + * suspend or we'll have issues running the pfuncs + */ + if (request_irq(host->irq, kw_i2c_irq, IRQF_NO_SUSPEND, + "keywest i2c", host)) + host->irq = 0; + + printk(KERN_INFO "KeyWest i2c @0x%08x irq %d %pOF\n", + *addrp, host->irq, np); + + return host; +} + + +static void __init kw_i2c_add(struct pmac_i2c_host_kw *host, + struct device_node *controller, + struct device_node *busnode, + int channel) +{ + struct pmac_i2c_bus *bus; + + bus = kzalloc(sizeof(struct pmac_i2c_bus), GFP_KERNEL); + if (bus == NULL) + return; + + bus->controller = of_node_get(controller); + bus->busnode = of_node_get(busnode); + bus->type = pmac_i2c_bus_keywest; + bus->hostdata = host; + bus->channel = channel; + bus->mode = pmac_i2c_mode_std; + bus->open = kw_i2c_open; + bus->close = kw_i2c_close; + bus->xfer = kw_i2c_xfer; + mutex_init(&bus->mutex); + lockdep_register_key(&bus->lock_key); + lockdep_set_class(&bus->mutex, &bus->lock_key); + if (controller == busnode) + bus->flags = pmac_i2c_multibus; + list_add(&bus->link, &pmac_i2c_busses); + + printk(KERN_INFO " channel %d bus %s\n", channel, + (controller == busnode) ? "<multibus>" : busnode->full_name); +} + +static void __init kw_i2c_probe(void) +{ + struct device_node *np, *child, *parent; + + /* Probe keywest-i2c busses */ + for_each_compatible_node(np, "i2c","keywest-i2c") { + struct pmac_i2c_host_kw *host; + int multibus; + + /* Found one, init a host structure */ + host = kw_i2c_host_init(np); + if (host == NULL) + continue; + + /* Now check if we have a multibus setup (old style) or if we + * have proper bus nodes. Note that the "new" way (proper bus + * nodes) might cause us to not create some busses that are + * kept hidden in the device-tree. In the future, we might + * want to work around that by creating busses without a node + * but not for now + */ + child = of_get_next_child(np, NULL); + multibus = !of_node_name_eq(child, "i2c-bus"); + of_node_put(child); + + /* For a multibus setup, we get the bus count based on the + * parent type + */ + if (multibus) { + int chans, i; + + parent = of_get_parent(np); + if (parent == NULL) + continue; + chans = parent->name[0] == 'u' ? 2 : 1; + for (i = 0; i < chans; i++) + kw_i2c_add(host, np, np, i); + } else { + for_each_child_of_node(np, child) { + const u32 *reg = of_get_property(child, + "reg", NULL); + if (reg == NULL) + continue; + kw_i2c_add(host, np, child, *reg); + } + } + } +} + + +/* + * + * PMU implementation + * + */ + +#ifdef CONFIG_ADB_PMU + +/* + * i2c command block to the PMU + */ +struct pmu_i2c_hdr { + u8 bus; + u8 mode; + u8 bus2; + u8 address; + u8 sub_addr; + u8 comb_addr; + u8 count; + u8 data[]; +}; + +static void pmu_i2c_complete(struct adb_request *req) +{ + complete(req->arg); +} + +static int pmu_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize, + u32 subaddr, u8 *data, int len) +{ + struct adb_request *req = bus->hostdata; + struct pmu_i2c_hdr *hdr = (struct pmu_i2c_hdr *)&req->data[1]; + struct completion comp; + int read = addrdir & 1; + int retry; + int rc = 0; + + /* For now, limit ourselves to 16 bytes transfers */ + if (len > 16) + return -EINVAL; + + init_completion(&comp); + + for (retry = 0; retry < 16; retry++) { + memset(req, 0, sizeof(struct adb_request)); + hdr->bus = bus->channel; + hdr->count = len; + + switch(bus->mode) { + case pmac_i2c_mode_std: + if (subsize != 0) + return -EINVAL; + hdr->address = addrdir; + hdr->mode = PMU_I2C_MODE_SIMPLE; + break; + case pmac_i2c_mode_stdsub: + case pmac_i2c_mode_combined: + if (subsize != 1) + return -EINVAL; + hdr->address = addrdir & 0xfe; + hdr->comb_addr = addrdir; + hdr->sub_addr = subaddr; + if (bus->mode == pmac_i2c_mode_stdsub) + hdr->mode = PMU_I2C_MODE_STDSUB; + else + hdr->mode = PMU_I2C_MODE_COMBINED; + break; + default: + return -EINVAL; + } + + reinit_completion(&comp); + req->data[0] = PMU_I2C_CMD; + req->reply[0] = 0xff; + req->nbytes = sizeof(struct pmu_i2c_hdr) + 1; + req->done = pmu_i2c_complete; + req->arg = ∁ + if (!read && len) { + memcpy(hdr->data, data, len); + req->nbytes += len; + } + rc = pmu_queue_request(req); + if (rc) + return rc; + wait_for_completion(&comp); + if (req->reply[0] == PMU_I2C_STATUS_OK) + break; + msleep(15); + } + if (req->reply[0] != PMU_I2C_STATUS_OK) + return -EIO; + + for (retry = 0; retry < 16; retry++) { + memset(req, 0, sizeof(struct adb_request)); + + /* I know that looks like a lot, slow as hell, but darwin + * does it so let's be on the safe side for now + */ + msleep(15); + + hdr->bus = PMU_I2C_BUS_STATUS; + + reinit_completion(&comp); + req->data[0] = PMU_I2C_CMD; + req->reply[0] = 0xff; + req->nbytes = 2; + req->done = pmu_i2c_complete; + req->arg = ∁ + rc = pmu_queue_request(req); + if (rc) + return rc; + wait_for_completion(&comp); + + if (req->reply[0] == PMU_I2C_STATUS_OK && !read) + return 0; + if (req->reply[0] == PMU_I2C_STATUS_DATAREAD && read) { + int rlen = req->reply_len - 1; + + if (rlen != len) { + printk(KERN_WARNING "low_i2c: PMU returned %d" + " bytes, expected %d !\n", rlen, len); + return -EIO; + } + if (len) + memcpy(data, &req->reply[1], len); + return 0; + } + } + return -EIO; +} + +static void __init pmu_i2c_probe(void) +{ + struct pmac_i2c_bus *bus; + struct device_node *busnode; + int channel, sz; + + if (!pmu_present()) + return; + + /* There might or might not be a "pmu-i2c" node, we use that + * or via-pmu itself, whatever we find. I haven't seen a machine + * with separate bus nodes, so we assume a multibus setup + */ + busnode = of_find_node_by_name(NULL, "pmu-i2c"); + if (busnode == NULL) + busnode = of_find_node_by_name(NULL, "via-pmu"); + if (busnode == NULL) + return; + + printk(KERN_INFO "PMU i2c %pOF\n", busnode); + + /* + * We add bus 1 and 2 only for now, bus 0 is "special" + */ + for (channel = 1; channel <= 2; channel++) { + sz = sizeof(struct pmac_i2c_bus) + sizeof(struct adb_request); + bus = kzalloc(sz, GFP_KERNEL); + if (bus == NULL) + return; + + bus->controller = busnode; + bus->busnode = busnode; + bus->type = pmac_i2c_bus_pmu; + bus->channel = channel; + bus->mode = pmac_i2c_mode_std; + bus->hostdata = bus + 1; + bus->xfer = pmu_i2c_xfer; + mutex_init(&bus->mutex); + lockdep_register_key(&bus->lock_key); + lockdep_set_class(&bus->mutex, &bus->lock_key); + bus->flags = pmac_i2c_multibus; + list_add(&bus->link, &pmac_i2c_busses); + + printk(KERN_INFO " channel %d bus <multibus>\n", channel); + } +} + +#endif /* CONFIG_ADB_PMU */ + + +/* + * + * SMU implementation + * + */ + +#ifdef CONFIG_PMAC_SMU + +static void smu_i2c_complete(struct smu_i2c_cmd *cmd, void *misc) +{ + complete(misc); +} + +static int smu_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize, + u32 subaddr, u8 *data, int len) +{ + struct smu_i2c_cmd *cmd = bus->hostdata; + struct completion comp; + int read = addrdir & 1; + int rc = 0; + + if ((read && len > SMU_I2C_READ_MAX) || + ((!read) && len > SMU_I2C_WRITE_MAX)) + return -EINVAL; + + memset(cmd, 0, sizeof(struct smu_i2c_cmd)); + cmd->info.bus = bus->channel; + cmd->info.devaddr = addrdir; + cmd->info.datalen = len; + + switch(bus->mode) { + case pmac_i2c_mode_std: + if (subsize != 0) + return -EINVAL; + cmd->info.type = SMU_I2C_TRANSFER_SIMPLE; + break; + case pmac_i2c_mode_stdsub: + case pmac_i2c_mode_combined: + if (subsize > 3 || subsize < 1) + return -EINVAL; + cmd->info.sublen = subsize; + /* that's big-endian only but heh ! */ + memcpy(&cmd->info.subaddr, ((char *)&subaddr) + (4 - subsize), + subsize); + if (bus->mode == pmac_i2c_mode_stdsub) + cmd->info.type = SMU_I2C_TRANSFER_STDSUB; + else + cmd->info.type = SMU_I2C_TRANSFER_COMBINED; + break; + default: + return -EINVAL; + } + if (!read && len) + memcpy(cmd->info.data, data, len); + + init_completion(&comp); + cmd->done = smu_i2c_complete; + cmd->misc = ∁ + rc = smu_queue_i2c(cmd); + if (rc < 0) + return rc; + wait_for_completion(&comp); + rc = cmd->status; + + if (read && len) + memcpy(data, cmd->info.data, len); + return rc < 0 ? rc : 0; +} + +static void __init smu_i2c_probe(void) +{ + struct device_node *controller, *busnode; + struct pmac_i2c_bus *bus; + const u32 *reg; + int sz; + + if (!smu_present()) + return; + + controller = of_find_node_by_name(NULL, "smu-i2c-control"); + if (controller == NULL) + controller = of_find_node_by_name(NULL, "smu"); + if (controller == NULL) + return; + + printk(KERN_INFO "SMU i2c %pOF\n", controller); + + /* Look for childs, note that they might not be of the right + * type as older device trees mix i2c busses and other things + * at the same level + */ + for_each_child_of_node(controller, busnode) { + if (!of_node_is_type(busnode, "i2c") && + !of_node_is_type(busnode, "i2c-bus")) + continue; + reg = of_get_property(busnode, "reg", NULL); + if (reg == NULL) + continue; + + sz = sizeof(struct pmac_i2c_bus) + sizeof(struct smu_i2c_cmd); + bus = kzalloc(sz, GFP_KERNEL); + if (bus == NULL) + return; + + bus->controller = controller; + bus->busnode = of_node_get(busnode); + bus->type = pmac_i2c_bus_smu; + bus->channel = *reg; + bus->mode = pmac_i2c_mode_std; + bus->hostdata = bus + 1; + bus->xfer = smu_i2c_xfer; + mutex_init(&bus->mutex); + lockdep_register_key(&bus->lock_key); + lockdep_set_class(&bus->mutex, &bus->lock_key); + bus->flags = 0; + list_add(&bus->link, &pmac_i2c_busses); + + printk(KERN_INFO " channel %x bus %pOF\n", + bus->channel, busnode); + } +} + +#endif /* CONFIG_PMAC_SMU */ + +/* + * + * Core code + * + */ + + +struct pmac_i2c_bus *pmac_i2c_find_bus(struct device_node *node) +{ + struct device_node *p = of_node_get(node); + struct device_node *prev = NULL; + struct pmac_i2c_bus *bus; + + while(p) { + list_for_each_entry(bus, &pmac_i2c_busses, link) { + if (p == bus->busnode) { + if (prev && bus->flags & pmac_i2c_multibus) { + const u32 *reg; + reg = of_get_property(prev, "reg", + NULL); + if (!reg) + continue; + if (((*reg) >> 8) != bus->channel) + continue; + } + of_node_put(p); + of_node_put(prev); + return bus; + } + } + of_node_put(prev); + prev = p; + p = of_get_parent(p); + } + return NULL; +} +EXPORT_SYMBOL_GPL(pmac_i2c_find_bus); + +u8 pmac_i2c_get_dev_addr(struct device_node *device) +{ + const u32 *reg = of_get_property(device, "reg", NULL); + + if (reg == NULL) + return 0; + + return (*reg) & 0xff; +} +EXPORT_SYMBOL_GPL(pmac_i2c_get_dev_addr); + +struct device_node *pmac_i2c_get_controller(struct pmac_i2c_bus *bus) +{ + return bus->controller; +} +EXPORT_SYMBOL_GPL(pmac_i2c_get_controller); + +struct device_node *pmac_i2c_get_bus_node(struct pmac_i2c_bus *bus) +{ + return bus->busnode; +} +EXPORT_SYMBOL_GPL(pmac_i2c_get_bus_node); + +int pmac_i2c_get_type(struct pmac_i2c_bus *bus) +{ + return bus->type; +} +EXPORT_SYMBOL_GPL(pmac_i2c_get_type); + +int pmac_i2c_get_flags(struct pmac_i2c_bus *bus) +{ + return bus->flags; +} +EXPORT_SYMBOL_GPL(pmac_i2c_get_flags); + +int pmac_i2c_get_channel(struct pmac_i2c_bus *bus) +{ + return bus->channel; +} +EXPORT_SYMBOL_GPL(pmac_i2c_get_channel); + + +struct i2c_adapter *pmac_i2c_get_adapter(struct pmac_i2c_bus *bus) +{ + return &bus->adapter; +} +EXPORT_SYMBOL_GPL(pmac_i2c_get_adapter); + +struct pmac_i2c_bus *pmac_i2c_adapter_to_bus(struct i2c_adapter *adapter) +{ + struct pmac_i2c_bus *bus; + + list_for_each_entry(bus, &pmac_i2c_busses, link) + if (&bus->adapter == adapter) + return bus; + return NULL; +} +EXPORT_SYMBOL_GPL(pmac_i2c_adapter_to_bus); + +int pmac_i2c_match_adapter(struct device_node *dev, struct i2c_adapter *adapter) +{ + struct pmac_i2c_bus *bus = pmac_i2c_find_bus(dev); + + if (bus == NULL) + return 0; + return (&bus->adapter == adapter); +} +EXPORT_SYMBOL_GPL(pmac_i2c_match_adapter); + +int pmac_low_i2c_lock(struct device_node *np) +{ + struct pmac_i2c_bus *bus, *found = NULL; + + list_for_each_entry(bus, &pmac_i2c_busses, link) { + if (np == bus->controller) { + found = bus; + break; + } + } + if (!found) + return -ENODEV; + return pmac_i2c_open(bus, 0); +} +EXPORT_SYMBOL_GPL(pmac_low_i2c_lock); + +int pmac_low_i2c_unlock(struct device_node *np) +{ + struct pmac_i2c_bus *bus, *found = NULL; + + list_for_each_entry(bus, &pmac_i2c_busses, link) { + if (np == bus->controller) { + found = bus; + break; + } + } + if (!found) + return -ENODEV; + pmac_i2c_close(bus); + return 0; +} +EXPORT_SYMBOL_GPL(pmac_low_i2c_unlock); + + +int pmac_i2c_open(struct pmac_i2c_bus *bus, int polled) +{ + int rc; + + mutex_lock(&bus->mutex); + bus->polled = polled || pmac_i2c_force_poll; + bus->opened = 1; + bus->mode = pmac_i2c_mode_std; + if (bus->open && (rc = bus->open(bus)) != 0) { + bus->opened = 0; + mutex_unlock(&bus->mutex); + return rc; + } + return 0; +} +EXPORT_SYMBOL_GPL(pmac_i2c_open); + +void pmac_i2c_close(struct pmac_i2c_bus *bus) +{ + WARN_ON(!bus->opened); + if (bus->close) + bus->close(bus); + bus->opened = 0; + mutex_unlock(&bus->mutex); +} +EXPORT_SYMBOL_GPL(pmac_i2c_close); + +int pmac_i2c_setmode(struct pmac_i2c_bus *bus, int mode) +{ + WARN_ON(!bus->opened); + + /* Report me if you see the error below as there might be a new + * "combined4" mode that I need to implement for the SMU bus + */ + if (mode < pmac_i2c_mode_dumb || mode > pmac_i2c_mode_combined) { + printk(KERN_ERR "low_i2c: Invalid mode %d requested on" + " bus %pOF !\n", mode, bus->busnode); + return -EINVAL; + } + bus->mode = mode; + + return 0; +} +EXPORT_SYMBOL_GPL(pmac_i2c_setmode); + +int pmac_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize, + u32 subaddr, u8 *data, int len) +{ + int rc; + + WARN_ON(!bus->opened); + + DBG("xfer() chan=%d, addrdir=0x%x, mode=%d, subsize=%d, subaddr=0x%x," + " %d bytes, bus %pOF\n", bus->channel, addrdir, bus->mode, subsize, + subaddr, len, bus->busnode); + + rc = bus->xfer(bus, addrdir, subsize, subaddr, data, len); + +#ifdef DEBUG + if (rc) + DBG("xfer error %d\n", rc); +#endif + return rc; +} +EXPORT_SYMBOL_GPL(pmac_i2c_xfer); + +/* some quirks for platform function decoding */ +enum { + pmac_i2c_quirk_invmask = 0x00000001u, + pmac_i2c_quirk_skip = 0x00000002u, +}; + +static void pmac_i2c_devscan(void (*callback)(struct device_node *dev, + int quirks)) +{ + struct pmac_i2c_bus *bus; + struct device_node *np; + static struct whitelist_ent { + char *name; + char *compatible; + int quirks; + } whitelist[] = { + /* XXX Study device-tree's & apple drivers are get the quirks + * right ! + */ + /* Workaround: It seems that running the clockspreading + * properties on the eMac will cause lockups during boot. + * The machine seems to work fine without that. So for now, + * let's make sure i2c-hwclock doesn't match about "imic" + * clocks and we'll figure out if we really need to do + * something special about those later. + */ + { "i2c-hwclock", "imic5002", pmac_i2c_quirk_skip }, + { "i2c-hwclock", "imic5003", pmac_i2c_quirk_skip }, + { "i2c-hwclock", NULL, pmac_i2c_quirk_invmask }, + { "i2c-cpu-voltage", NULL, 0}, + { "temp-monitor", NULL, 0 }, + { "supply-monitor", NULL, 0 }, + { NULL, NULL, 0 }, + }; + + /* Only some devices need to have platform functions instantiated + * here. For now, we have a table. Others, like 9554 i2c GPIOs used + * on Xserve, if we ever do a driver for them, will use their own + * platform function instance + */ + list_for_each_entry(bus, &pmac_i2c_busses, link) { + for_each_child_of_node(bus->busnode, np) { + struct whitelist_ent *p; + /* If multibus, check if device is on that bus */ + if (bus->flags & pmac_i2c_multibus) + if (bus != pmac_i2c_find_bus(np)) + continue; + for (p = whitelist; p->name != NULL; p++) { + if (!of_node_name_eq(np, p->name)) + continue; + if (p->compatible && + !of_device_is_compatible(np, p->compatible)) + continue; + if (p->quirks & pmac_i2c_quirk_skip) + break; + callback(np, p->quirks); + break; + } + } + } +} + +#define MAX_I2C_DATA 64 + +struct pmac_i2c_pf_inst +{ + struct pmac_i2c_bus *bus; + u8 addr; + u8 buffer[MAX_I2C_DATA]; + u8 scratch[MAX_I2C_DATA]; + int bytes; + int quirks; +}; + +static void* pmac_i2c_do_begin(struct pmf_function *func, struct pmf_args *args) +{ + struct pmac_i2c_pf_inst *inst; + struct pmac_i2c_bus *bus; + + bus = pmac_i2c_find_bus(func->node); + if (bus == NULL) { + printk(KERN_ERR "low_i2c: Can't find bus for %pOF (pfunc)\n", + func->node); + return NULL; + } + if (pmac_i2c_open(bus, 0)) { + printk(KERN_ERR "low_i2c: Can't open i2c bus for %pOF (pfunc)\n", + func->node); + return NULL; + } + + /* XXX might need GFP_ATOMIC when called during the suspend process, + * but then, there are already lots of issues with suspending when + * near OOM that need to be resolved, the allocator itself should + * probably make GFP_NOIO implicit during suspend + */ + inst = kzalloc(sizeof(struct pmac_i2c_pf_inst), GFP_KERNEL); + if (inst == NULL) { + pmac_i2c_close(bus); + return NULL; + } + inst->bus = bus; + inst->addr = pmac_i2c_get_dev_addr(func->node); + inst->quirks = (int)(long)func->driver_data; + return inst; +} + +static void pmac_i2c_do_end(struct pmf_function *func, void *instdata) +{ + struct pmac_i2c_pf_inst *inst = instdata; + + if (inst == NULL) + return; + pmac_i2c_close(inst->bus); + kfree(inst); +} + +static int pmac_i2c_do_read(PMF_STD_ARGS, u32 len) +{ + struct pmac_i2c_pf_inst *inst = instdata; + + inst->bytes = len; + return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 0, 0, + inst->buffer, len); +} + +static int pmac_i2c_do_write(PMF_STD_ARGS, u32 len, const u8 *data) +{ + struct pmac_i2c_pf_inst *inst = instdata; + + return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0, + (u8 *)data, len); +} + +/* This function is used to do the masking & OR'ing for the "rmw" type + * callbacks. Ze should apply the mask and OR in the values in the + * buffer before writing back. The problem is that it seems that + * various darwin drivers implement the mask/or differently, thus + * we need to check the quirks first + */ +static void pmac_i2c_do_apply_rmw(struct pmac_i2c_pf_inst *inst, + u32 len, const u8 *mask, const u8 *val) +{ + int i; + + if (inst->quirks & pmac_i2c_quirk_invmask) { + for (i = 0; i < len; i ++) + inst->scratch[i] = (inst->buffer[i] & mask[i]) | val[i]; + } else { + for (i = 0; i < len; i ++) + inst->scratch[i] = (inst->buffer[i] & ~mask[i]) + | (val[i] & mask[i]); + } +} + +static int pmac_i2c_do_rmw(PMF_STD_ARGS, u32 masklen, u32 valuelen, + u32 totallen, const u8 *maskdata, + const u8 *valuedata) +{ + struct pmac_i2c_pf_inst *inst = instdata; + + if (masklen > inst->bytes || valuelen > inst->bytes || + totallen > inst->bytes || valuelen > masklen) + return -EINVAL; + + pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata); + + return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 0, 0, + inst->scratch, totallen); +} + +static int pmac_i2c_do_read_sub(PMF_STD_ARGS, u8 subaddr, u32 len) +{ + struct pmac_i2c_pf_inst *inst = instdata; + + inst->bytes = len; + return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_read, 1, subaddr, + inst->buffer, len); +} + +static int pmac_i2c_do_write_sub(PMF_STD_ARGS, u8 subaddr, u32 len, + const u8 *data) +{ + struct pmac_i2c_pf_inst *inst = instdata; + + return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1, + subaddr, (u8 *)data, len); +} + +static int pmac_i2c_do_set_mode(PMF_STD_ARGS, int mode) +{ + struct pmac_i2c_pf_inst *inst = instdata; + + return pmac_i2c_setmode(inst->bus, mode); +} + +static int pmac_i2c_do_rmw_sub(PMF_STD_ARGS, u8 subaddr, u32 masklen, + u32 valuelen, u32 totallen, const u8 *maskdata, + const u8 *valuedata) +{ + struct pmac_i2c_pf_inst *inst = instdata; + + if (masklen > inst->bytes || valuelen > inst->bytes || + totallen > inst->bytes || valuelen > masklen) + return -EINVAL; + + pmac_i2c_do_apply_rmw(inst, masklen, maskdata, valuedata); + + return pmac_i2c_xfer(inst->bus, inst->addr | pmac_i2c_write, 1, + subaddr, inst->scratch, totallen); +} + +static int pmac_i2c_do_mask_and_comp(PMF_STD_ARGS, u32 len, + const u8 *maskdata, + const u8 *valuedata) +{ + struct pmac_i2c_pf_inst *inst = instdata; + int i, match; + + /* Get return value pointer, it's assumed to be a u32 */ + if (!args || !args->count || !args->u[0].p) + return -EINVAL; + + /* Check buffer */ + if (len > inst->bytes) + return -EINVAL; + + for (i = 0, match = 1; match && i < len; i ++) + if ((inst->buffer[i] & maskdata[i]) != valuedata[i]) + match = 0; + *args->u[0].p = match; + return 0; +} + +static int pmac_i2c_do_delay(PMF_STD_ARGS, u32 duration) +{ + msleep((duration + 999) / 1000); + return 0; +} + + +static struct pmf_handlers pmac_i2c_pfunc_handlers = { + .begin = pmac_i2c_do_begin, + .end = pmac_i2c_do_end, + .read_i2c = pmac_i2c_do_read, + .write_i2c = pmac_i2c_do_write, + .rmw_i2c = pmac_i2c_do_rmw, + .read_i2c_sub = pmac_i2c_do_read_sub, + .write_i2c_sub = pmac_i2c_do_write_sub, + .rmw_i2c_sub = pmac_i2c_do_rmw_sub, + .set_i2c_mode = pmac_i2c_do_set_mode, + .mask_and_compare = pmac_i2c_do_mask_and_comp, + .delay = pmac_i2c_do_delay, +}; + +static void __init pmac_i2c_dev_create(struct device_node *np, int quirks) +{ + DBG("dev_create(%pOF)\n", np); + + pmf_register_driver(np, &pmac_i2c_pfunc_handlers, + (void *)(long)quirks); +} + +static void __init pmac_i2c_dev_init(struct device_node *np, int quirks) +{ + DBG("dev_create(%pOF)\n", np); + + pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_INIT, NULL); +} + +static void pmac_i2c_dev_suspend(struct device_node *np, int quirks) +{ + DBG("dev_suspend(%pOF)\n", np); + pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_SLEEP, NULL); +} + +static void pmac_i2c_dev_resume(struct device_node *np, int quirks) +{ + DBG("dev_resume(%pOF)\n", np); + pmf_do_functions(np, NULL, 0, PMF_FLAGS_ON_WAKE, NULL); +} + +void pmac_pfunc_i2c_suspend(void) +{ + pmac_i2c_devscan(pmac_i2c_dev_suspend); +} + +void pmac_pfunc_i2c_resume(void) +{ + pmac_i2c_devscan(pmac_i2c_dev_resume); +} + +/* + * Initialize us: probe all i2c busses on the machine, instantiate + * busses and platform functions as needed. + */ +/* This is non-static as it might be called early by smp code */ +int __init pmac_i2c_init(void) +{ + static int i2c_inited; + + if (i2c_inited) + return 0; + i2c_inited = 1; + + /* Probe keywest-i2c busses */ + kw_i2c_probe(); + +#ifdef CONFIG_ADB_PMU + /* Probe PMU i2c busses */ + pmu_i2c_probe(); +#endif + +#ifdef CONFIG_PMAC_SMU + /* Probe SMU i2c busses */ + smu_i2c_probe(); +#endif + + /* Now add plaform functions for some known devices */ + pmac_i2c_devscan(pmac_i2c_dev_create); + + return 0; +} +machine_arch_initcall(powermac, pmac_i2c_init); + +/* Since pmac_i2c_init can be called too early for the platform device + * registration, we need to do it at a later time. In our case, subsys + * happens to fit well, though I agree it's a bit of a hack... + */ +static int __init pmac_i2c_create_platform_devices(void) +{ + struct pmac_i2c_bus *bus; + int i = 0; + + /* In the case where we are initialized from smp_init(), we must + * not use the timer (and thus the irq). It's safe from now on + * though + */ + pmac_i2c_force_poll = 0; + + /* Create platform devices */ + list_for_each_entry(bus, &pmac_i2c_busses, link) { + bus->platform_dev = + platform_device_alloc("i2c-powermac", i++); + if (bus->platform_dev == NULL) + return -ENOMEM; + bus->platform_dev->dev.platform_data = bus; + bus->platform_dev->dev.of_node = bus->busnode; + platform_device_add(bus->platform_dev); + } + + /* Now call platform "init" functions */ + pmac_i2c_devscan(pmac_i2c_dev_init); + + return 0; +} +machine_subsys_initcall(powermac, pmac_i2c_create_platform_devices); |