|  | /* | 
|  | * SuperH Mobile I2C Controller | 
|  | * | 
|  | * Copyright (C) 2008 Magnus Damm | 
|  | * | 
|  | * Portions of the code based on out-of-tree driver i2c-sh7343.c | 
|  | * Copyright (c) 2006 Carlos Munoz <carlos@kenati.com> | 
|  | * | 
|  | * 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 | 
|  | * | 
|  | * This program is distributed in the hope that it will be useful, | 
|  | * but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
|  | * GNU General Public License for more details. | 
|  | * | 
|  | * You should have received a copy of the GNU General Public License | 
|  | * along with this program; if not, write to the Free Software | 
|  | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA | 
|  | */ | 
|  |  | 
|  | #include <linux/kernel.h> | 
|  | #include <linux/module.h> | 
|  | #include <linux/init.h> | 
|  | #include <linux/delay.h> | 
|  | #include <linux/platform_device.h> | 
|  | #include <linux/interrupt.h> | 
|  | #include <linux/i2c.h> | 
|  | #include <linux/err.h> | 
|  | #include <linux/pm_runtime.h> | 
|  | #include <linux/clk.h> | 
|  | #include <linux/io.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/i2c/i2c-sh_mobile.h> | 
|  |  | 
|  | /* Transmit operation:                                                      */ | 
|  | /*                                                                          */ | 
|  | /* 0 byte transmit                                                          */ | 
|  | /* BUS:     S     A8     ACK   P                                            */ | 
|  | /* IRQ:       DTE   WAIT                                                    */ | 
|  | /* ICIC:                                                                    */ | 
|  | /* ICCR: 0x94 0x90                                                          */ | 
|  | /* ICDR:      A8                                                            */ | 
|  | /*                                                                          */ | 
|  | /* 1 byte transmit                                                          */ | 
|  | /* BUS:     S     A8     ACK   D8(1)   ACK   P                              */ | 
|  | /* IRQ:       DTE   WAIT         WAIT                                       */ | 
|  | /* ICIC:      -DTE                                                          */ | 
|  | /* ICCR: 0x94       0x90                                                    */ | 
|  | /* ICDR:      A8    D8(1)                                                   */ | 
|  | /*                                                                          */ | 
|  | /* 2 byte transmit                                                          */ | 
|  | /* BUS:     S     A8     ACK   D8(1)   ACK   D8(2)   ACK   P                */ | 
|  | /* IRQ:       DTE   WAIT         WAIT          WAIT                         */ | 
|  | /* ICIC:      -DTE                                                          */ | 
|  | /* ICCR: 0x94                    0x90                                       */ | 
|  | /* ICDR:      A8    D8(1)        D8(2)                                      */ | 
|  | /*                                                                          */ | 
|  | /* 3 bytes or more, +---------+ gets repeated                               */ | 
|  | /*                                                                          */ | 
|  | /*                                                                          */ | 
|  | /* Receive operation:                                                       */ | 
|  | /*                                                                          */ | 
|  | /* 0 byte receive - not supported since slave may hold SDA low              */ | 
|  | /*                                                                          */ | 
|  | /* 1 byte receive       [TX] | [RX]                                         */ | 
|  | /* BUS:     S     A8     ACK | D8(1)   ACK   P                              */ | 
|  | /* IRQ:       DTE   WAIT     |   WAIT     DTE                               */ | 
|  | /* ICIC:      -DTE           |   +DTE                                       */ | 
|  | /* ICCR: 0x94       0x81     |   0xc0                                       */ | 
|  | /* ICDR:      A8             |            D8(1)                             */ | 
|  | /*                                                                          */ | 
|  | /* 2 byte receive        [TX]| [RX]                                         */ | 
|  | /* BUS:     S     A8     ACK | D8(1)   ACK   D8(2)   ACK   P                */ | 
|  | /* IRQ:       DTE   WAIT     |   WAIT          WAIT     DTE                 */ | 
|  | /* ICIC:      -DTE           |                 +DTE                         */ | 
|  | /* ICCR: 0x94       0x81     |                 0xc0                         */ | 
|  | /* ICDR:      A8             |                 D8(1)    D8(2)               */ | 
|  | /*                                                                          */ | 
|  | /* 3 byte receive       [TX] | [RX]                                         */ | 
|  | /* BUS:     S     A8     ACK | D8(1)   ACK   D8(2)   ACK   D8(3)   ACK    P */ | 
|  | /* IRQ:       DTE   WAIT     |   WAIT          WAIT         WAIT      DTE   */ | 
|  | /* ICIC:      -DTE           |                              +DTE            */ | 
|  | /* ICCR: 0x94       0x81     |                              0xc0            */ | 
|  | /* ICDR:      A8             |                 D8(1)        D8(2)     D8(3) */ | 
|  | /*                                                                          */ | 
|  | /* 4 bytes or more, this part is repeated    +---------+                    */ | 
|  | /*                                                                          */ | 
|  | /*                                                                          */ | 
|  | /* Interrupt order and BUSY flag                                            */ | 
|  | /*     ___                                                 _                */ | 
|  | /* SDA ___\___XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXAAAAAAAAA___/                 */ | 
|  | /* SCL      \_/1\_/2\_/3\_/4\_/5\_/6\_/7\_/8\___/9\_____/                   */ | 
|  | /*                                                                          */ | 
|  | /*        S   D7  D6  D5  D4  D3  D2  D1  D0              P                 */ | 
|  | /*                                           ___                            */ | 
|  | /* WAIT IRQ ________________________________/   \___________                */ | 
|  | /* TACK IRQ ____________________________________/   \_______                */ | 
|  | /* DTE  IRQ __________________________________________/   \_                */ | 
|  | /* AL   IRQ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX                */ | 
|  | /*         _______________________________________________                  */ | 
|  | /* BUSY __/                                               \_                */ | 
|  | /*                                                                          */ | 
|  |  | 
|  | enum sh_mobile_i2c_op { | 
|  | OP_START = 0, | 
|  | OP_TX_FIRST, | 
|  | OP_TX, | 
|  | OP_TX_STOP, | 
|  | OP_TX_TO_RX, | 
|  | OP_RX, | 
|  | OP_RX_STOP, | 
|  | OP_RX_STOP_DATA, | 
|  | }; | 
|  |  | 
|  | struct sh_mobile_i2c_data { | 
|  | struct device *dev; | 
|  | void __iomem *reg; | 
|  | struct i2c_adapter adap; | 
|  | unsigned long bus_speed; | 
|  | struct clk *clk; | 
|  | u_int8_t icic; | 
|  | u_int8_t iccl; | 
|  | u_int8_t icch; | 
|  | u_int8_t flags; | 
|  |  | 
|  | spinlock_t lock; | 
|  | wait_queue_head_t wait; | 
|  | struct i2c_msg *msg; | 
|  | int pos; | 
|  | int sr; | 
|  | }; | 
|  |  | 
|  | #define IIC_FLAG_HAS_ICIC67	(1 << 0) | 
|  |  | 
|  | #define NORMAL_SPEED		100000 /* FAST_SPEED 400000 */ | 
|  |  | 
|  | /* Register offsets */ | 
|  | #define ICDR			0x00 | 
|  | #define ICCR			0x04 | 
|  | #define ICSR			0x08 | 
|  | #define ICIC			0x0c | 
|  | #define ICCL			0x10 | 
|  | #define ICCH			0x14 | 
|  |  | 
|  | /* Register bits */ | 
|  | #define ICCR_ICE		0x80 | 
|  | #define ICCR_RACK		0x40 | 
|  | #define ICCR_TRS		0x10 | 
|  | #define ICCR_BBSY		0x04 | 
|  | #define ICCR_SCP		0x01 | 
|  |  | 
|  | #define ICSR_SCLM		0x80 | 
|  | #define ICSR_SDAM		0x40 | 
|  | #define SW_DONE			0x20 | 
|  | #define ICSR_BUSY		0x10 | 
|  | #define ICSR_AL			0x08 | 
|  | #define ICSR_TACK		0x04 | 
|  | #define ICSR_WAIT		0x02 | 
|  | #define ICSR_DTE		0x01 | 
|  |  | 
|  | #define ICIC_ICCLB8		0x80 | 
|  | #define ICIC_ICCHB8		0x40 | 
|  | #define ICIC_ALE		0x08 | 
|  | #define ICIC_TACKE		0x04 | 
|  | #define ICIC_WAITE		0x02 | 
|  | #define ICIC_DTEE		0x01 | 
|  |  | 
|  | static void iic_wr(struct sh_mobile_i2c_data *pd, int offs, unsigned char data) | 
|  | { | 
|  | if (offs == ICIC) | 
|  | data |= pd->icic; | 
|  |  | 
|  | iowrite8(data, pd->reg + offs); | 
|  | } | 
|  |  | 
|  | static unsigned char iic_rd(struct sh_mobile_i2c_data *pd, int offs) | 
|  | { | 
|  | return ioread8(pd->reg + offs); | 
|  | } | 
|  |  | 
|  | static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs, | 
|  | unsigned char set, unsigned char clr) | 
|  | { | 
|  | iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr); | 
|  | } | 
|  |  | 
|  | static void activate_ch(struct sh_mobile_i2c_data *pd) | 
|  | { | 
|  | unsigned long i2c_clk; | 
|  | u_int32_t num; | 
|  | u_int32_t denom; | 
|  | u_int32_t tmp; | 
|  |  | 
|  | /* Wake up device and enable clock */ | 
|  | pm_runtime_get_sync(pd->dev); | 
|  | clk_enable(pd->clk); | 
|  |  | 
|  | /* Get clock rate after clock is enabled */ | 
|  | i2c_clk = clk_get_rate(pd->clk); | 
|  |  | 
|  | /* Calculate the value for iccl. From the data sheet: | 
|  | * iccl = (p clock / transfer rate) * (L / (L + H)) | 
|  | * where L and H are the SCL low/high ratio (5/4 in this case). | 
|  | * We also round off the result. | 
|  | */ | 
|  | num = i2c_clk * 5; | 
|  | denom = pd->bus_speed * 9; | 
|  | tmp = num * 10 / denom; | 
|  | if (tmp % 10 >= 5) | 
|  | pd->iccl = (u_int8_t)((num/denom) + 1); | 
|  | else | 
|  | pd->iccl = (u_int8_t)(num/denom); | 
|  |  | 
|  | /* one more bit of ICCL in ICIC */ | 
|  | if (pd->flags & IIC_FLAG_HAS_ICIC67) { | 
|  | if ((num/denom) > 0xff) | 
|  | pd->icic |= ICIC_ICCLB8; | 
|  | else | 
|  | pd->icic &= ~ICIC_ICCLB8; | 
|  | } | 
|  |  | 
|  | /* Calculate the value for icch. From the data sheet: | 
|  | icch = (p clock / transfer rate) * (H / (L + H)) */ | 
|  | num = i2c_clk * 4; | 
|  | tmp = num * 10 / denom; | 
|  | if (tmp % 10 >= 5) | 
|  | pd->icch = (u_int8_t)((num/denom) + 1); | 
|  | else | 
|  | pd->icch = (u_int8_t)(num/denom); | 
|  |  | 
|  | /* one more bit of ICCH in ICIC */ | 
|  | if (pd->flags & IIC_FLAG_HAS_ICIC67) { | 
|  | if ((num/denom) > 0xff) | 
|  | pd->icic |= ICIC_ICCHB8; | 
|  | else | 
|  | pd->icic &= ~ICIC_ICCHB8; | 
|  | } | 
|  |  | 
|  | /* Enable channel and configure rx ack */ | 
|  | iic_set_clr(pd, ICCR, ICCR_ICE, 0); | 
|  |  | 
|  | /* Mask all interrupts */ | 
|  | iic_wr(pd, ICIC, 0); | 
|  |  | 
|  | /* Set the clock */ | 
|  | iic_wr(pd, ICCL, pd->iccl); | 
|  | iic_wr(pd, ICCH, pd->icch); | 
|  | } | 
|  |  | 
|  | static void deactivate_ch(struct sh_mobile_i2c_data *pd) | 
|  | { | 
|  | /* Clear/disable interrupts */ | 
|  | iic_wr(pd, ICSR, 0); | 
|  | iic_wr(pd, ICIC, 0); | 
|  |  | 
|  | /* Disable channel */ | 
|  | iic_set_clr(pd, ICCR, 0, ICCR_ICE); | 
|  |  | 
|  | /* Disable clock and mark device as idle */ | 
|  | clk_disable(pd->clk); | 
|  | pm_runtime_put_sync(pd->dev); | 
|  | } | 
|  |  | 
|  | static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, | 
|  | enum sh_mobile_i2c_op op, unsigned char data) | 
|  | { | 
|  | unsigned char ret = 0; | 
|  | unsigned long flags; | 
|  |  | 
|  | dev_dbg(pd->dev, "op %d, data in 0x%02x\n", op, data); | 
|  |  | 
|  | spin_lock_irqsave(&pd->lock, flags); | 
|  |  | 
|  | switch (op) { | 
|  | case OP_START: /* issue start and trigger DTE interrupt */ | 
|  | iic_wr(pd, ICCR, 0x94); | 
|  | break; | 
|  | case OP_TX_FIRST: /* disable DTE interrupt and write data */ | 
|  | iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE); | 
|  | iic_wr(pd, ICDR, data); | 
|  | break; | 
|  | case OP_TX: /* write data */ | 
|  | iic_wr(pd, ICDR, data); | 
|  | break; | 
|  | case OP_TX_STOP: /* write data and issue a stop afterwards */ | 
|  | iic_wr(pd, ICDR, data); | 
|  | iic_wr(pd, ICCR, 0x90); | 
|  | break; | 
|  | case OP_TX_TO_RX: /* select read mode */ | 
|  | iic_wr(pd, ICCR, 0x81); | 
|  | break; | 
|  | case OP_RX: /* just read data */ | 
|  | ret = iic_rd(pd, ICDR); | 
|  | break; | 
|  | case OP_RX_STOP: /* enable DTE interrupt, issue stop */ | 
|  | iic_wr(pd, ICIC, | 
|  | ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); | 
|  | iic_wr(pd, ICCR, 0xc0); | 
|  | break; | 
|  | case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */ | 
|  | iic_wr(pd, ICIC, | 
|  | ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); | 
|  | ret = iic_rd(pd, ICDR); | 
|  | iic_wr(pd, ICCR, 0xc0); | 
|  | break; | 
|  | } | 
|  |  | 
|  | spin_unlock_irqrestore(&pd->lock, flags); | 
|  |  | 
|  | dev_dbg(pd->dev, "op %d, data out 0x%02x\n", op, ret); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int sh_mobile_i2c_is_first_byte(struct sh_mobile_i2c_data *pd) | 
|  | { | 
|  | if (pd->pos == -1) | 
|  | return 1; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int sh_mobile_i2c_is_last_byte(struct sh_mobile_i2c_data *pd) | 
|  | { | 
|  | if (pd->pos == (pd->msg->len - 1)) | 
|  | return 1; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void sh_mobile_i2c_get_data(struct sh_mobile_i2c_data *pd, | 
|  | unsigned char *buf) | 
|  | { | 
|  | switch (pd->pos) { | 
|  | case -1: | 
|  | *buf = (pd->msg->addr & 0x7f) << 1; | 
|  | *buf |= (pd->msg->flags & I2C_M_RD) ? 1 : 0; | 
|  | break; | 
|  | default: | 
|  | *buf = pd->msg->buf[pd->pos]; | 
|  | } | 
|  | } | 
|  |  | 
|  | static int sh_mobile_i2c_isr_tx(struct sh_mobile_i2c_data *pd) | 
|  | { | 
|  | unsigned char data; | 
|  |  | 
|  | if (pd->pos == pd->msg->len) | 
|  | return 1; | 
|  |  | 
|  | sh_mobile_i2c_get_data(pd, &data); | 
|  |  | 
|  | if (sh_mobile_i2c_is_last_byte(pd)) | 
|  | i2c_op(pd, OP_TX_STOP, data); | 
|  | else if (sh_mobile_i2c_is_first_byte(pd)) | 
|  | i2c_op(pd, OP_TX_FIRST, data); | 
|  | else | 
|  | i2c_op(pd, OP_TX, data); | 
|  |  | 
|  | pd->pos++; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd) | 
|  | { | 
|  | unsigned char data; | 
|  | int real_pos; | 
|  |  | 
|  | do { | 
|  | if (pd->pos <= -1) { | 
|  | sh_mobile_i2c_get_data(pd, &data); | 
|  |  | 
|  | if (sh_mobile_i2c_is_first_byte(pd)) | 
|  | i2c_op(pd, OP_TX_FIRST, data); | 
|  | else | 
|  | i2c_op(pd, OP_TX, data); | 
|  | break; | 
|  | } | 
|  |  | 
|  | if (pd->pos == 0) { | 
|  | i2c_op(pd, OP_TX_TO_RX, 0); | 
|  | break; | 
|  | } | 
|  |  | 
|  | real_pos = pd->pos - 2; | 
|  |  | 
|  | if (pd->pos == pd->msg->len) { | 
|  | if (real_pos < 0) { | 
|  | i2c_op(pd, OP_RX_STOP, 0); | 
|  | break; | 
|  | } | 
|  | data = i2c_op(pd, OP_RX_STOP_DATA, 0); | 
|  | } else | 
|  | data = i2c_op(pd, OP_RX, 0); | 
|  |  | 
|  | if (real_pos >= 0) | 
|  | pd->msg->buf[real_pos] = data; | 
|  | } while (0); | 
|  |  | 
|  | pd->pos++; | 
|  | return pd->pos == (pd->msg->len + 2); | 
|  | } | 
|  |  | 
|  | static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id) | 
|  | { | 
|  | struct platform_device *dev = dev_id; | 
|  | struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev); | 
|  | unsigned char sr; | 
|  | int wakeup; | 
|  |  | 
|  | sr = iic_rd(pd, ICSR); | 
|  | pd->sr |= sr; /* remember state */ | 
|  |  | 
|  | dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr, | 
|  | (pd->msg->flags & I2C_M_RD) ? "read" : "write", | 
|  | pd->pos, pd->msg->len); | 
|  |  | 
|  | if (sr & (ICSR_AL | ICSR_TACK)) { | 
|  | /* don't interrupt transaction - continue to issue stop */ | 
|  | iic_wr(pd, ICSR, sr & ~(ICSR_AL | ICSR_TACK)); | 
|  | wakeup = 0; | 
|  | } else if (pd->msg->flags & I2C_M_RD) | 
|  | wakeup = sh_mobile_i2c_isr_rx(pd); | 
|  | else | 
|  | wakeup = sh_mobile_i2c_isr_tx(pd); | 
|  |  | 
|  | if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */ | 
|  | iic_wr(pd, ICSR, sr & ~ICSR_WAIT); | 
|  |  | 
|  | if (wakeup) { | 
|  | pd->sr |= SW_DONE; | 
|  | wake_up(&pd->wait); | 
|  | } | 
|  |  | 
|  | return IRQ_HANDLED; | 
|  | } | 
|  |  | 
|  | static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg) | 
|  | { | 
|  | if (usr_msg->len == 0 && (usr_msg->flags & I2C_M_RD)) { | 
|  | dev_err(pd->dev, "Unsupported zero length i2c read\n"); | 
|  | return -EIO; | 
|  | } | 
|  |  | 
|  | /* Initialize channel registers */ | 
|  | iic_set_clr(pd, ICCR, 0, ICCR_ICE); | 
|  |  | 
|  | /* Enable channel and configure rx ack */ | 
|  | iic_set_clr(pd, ICCR, ICCR_ICE, 0); | 
|  |  | 
|  | /* Set the clock */ | 
|  | iic_wr(pd, ICCL, pd->iccl); | 
|  | iic_wr(pd, ICCH, pd->icch); | 
|  |  | 
|  | pd->msg = usr_msg; | 
|  | pd->pos = -1; | 
|  | pd->sr = 0; | 
|  |  | 
|  | /* Enable all interrupts to begin with */ | 
|  | iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter, | 
|  | struct i2c_msg *msgs, | 
|  | int num) | 
|  | { | 
|  | struct sh_mobile_i2c_data *pd = i2c_get_adapdata(adapter); | 
|  | struct i2c_msg	*msg; | 
|  | int err = 0; | 
|  | u_int8_t val; | 
|  | int i, k, retry_count; | 
|  |  | 
|  | activate_ch(pd); | 
|  |  | 
|  | /* Process all messages */ | 
|  | for (i = 0; i < num; i++) { | 
|  | msg = &msgs[i]; | 
|  |  | 
|  | err = start_ch(pd, msg); | 
|  | if (err) | 
|  | break; | 
|  |  | 
|  | i2c_op(pd, OP_START, 0); | 
|  |  | 
|  | /* The interrupt handler takes care of the rest... */ | 
|  | k = wait_event_timeout(pd->wait, | 
|  | pd->sr & (ICSR_TACK | SW_DONE), | 
|  | 5 * HZ); | 
|  | if (!k) | 
|  | dev_err(pd->dev, "Transfer request timed out\n"); | 
|  |  | 
|  | retry_count = 1000; | 
|  | again: | 
|  | val = iic_rd(pd, ICSR); | 
|  |  | 
|  | dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr); | 
|  |  | 
|  | /* the interrupt handler may wake us up before the | 
|  | * transfer is finished, so poll the hardware | 
|  | * until we're done. | 
|  | */ | 
|  | if (val & ICSR_BUSY) { | 
|  | udelay(10); | 
|  | if (retry_count--) | 
|  | goto again; | 
|  |  | 
|  | err = -EIO; | 
|  | dev_err(pd->dev, "Polling timed out\n"); | 
|  | break; | 
|  | } | 
|  |  | 
|  | /* handle missing acknowledge and arbitration lost */ | 
|  | if ((val | pd->sr) & (ICSR_TACK | ICSR_AL)) { | 
|  | err = -EIO; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | deactivate_ch(pd); | 
|  |  | 
|  | if (!err) | 
|  | err = num; | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static u32 sh_mobile_i2c_func(struct i2c_adapter *adapter) | 
|  | { | 
|  | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; | 
|  | } | 
|  |  | 
|  | static struct i2c_algorithm sh_mobile_i2c_algorithm = { | 
|  | .functionality	= sh_mobile_i2c_func, | 
|  | .master_xfer	= sh_mobile_i2c_xfer, | 
|  | }; | 
|  |  | 
|  | static int sh_mobile_i2c_hook_irqs(struct platform_device *dev, int hook) | 
|  | { | 
|  | struct resource *res; | 
|  | int ret = -ENXIO; | 
|  | int n, k = 0; | 
|  |  | 
|  | while ((res = platform_get_resource(dev, IORESOURCE_IRQ, k))) { | 
|  | for (n = res->start; hook && n <= res->end; n++) { | 
|  | if (request_irq(n, sh_mobile_i2c_isr, 0, | 
|  | dev_name(&dev->dev), dev)) { | 
|  | for (n--; n >= res->start; n--) | 
|  | free_irq(n, dev); | 
|  |  | 
|  | goto rollback; | 
|  | } | 
|  | } | 
|  | k++; | 
|  | } | 
|  |  | 
|  | if (hook) | 
|  | return k > 0 ? 0 : -ENOENT; | 
|  |  | 
|  | ret = 0; | 
|  |  | 
|  | rollback: | 
|  | k--; | 
|  |  | 
|  | while (k >= 0) { | 
|  | res = platform_get_resource(dev, IORESOURCE_IRQ, k); | 
|  | for (n = res->start; n <= res->end; n++) | 
|  | free_irq(n, dev); | 
|  |  | 
|  | k--; | 
|  | } | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int sh_mobile_i2c_probe(struct platform_device *dev) | 
|  | { | 
|  | struct i2c_sh_mobile_platform_data *pdata = dev->dev.platform_data; | 
|  | struct sh_mobile_i2c_data *pd; | 
|  | struct i2c_adapter *adap; | 
|  | struct resource *res; | 
|  | int size; | 
|  | int ret; | 
|  |  | 
|  | pd = kzalloc(sizeof(struct sh_mobile_i2c_data), GFP_KERNEL); | 
|  | if (pd == NULL) { | 
|  | dev_err(&dev->dev, "cannot allocate private data\n"); | 
|  | return -ENOMEM; | 
|  | } | 
|  |  | 
|  | pd->clk = clk_get(&dev->dev, NULL); | 
|  | if (IS_ERR(pd->clk)) { | 
|  | dev_err(&dev->dev, "cannot get clock\n"); | 
|  | ret = PTR_ERR(pd->clk); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | ret = sh_mobile_i2c_hook_irqs(dev, 1); | 
|  | if (ret) { | 
|  | dev_err(&dev->dev, "cannot request IRQ\n"); | 
|  | goto err_clk; | 
|  | } | 
|  |  | 
|  | pd->dev = &dev->dev; | 
|  | platform_set_drvdata(dev, pd); | 
|  |  | 
|  | res = platform_get_resource(dev, IORESOURCE_MEM, 0); | 
|  | if (res == NULL) { | 
|  | dev_err(&dev->dev, "cannot find IO resource\n"); | 
|  | ret = -ENOENT; | 
|  | goto err_irq; | 
|  | } | 
|  |  | 
|  | size = resource_size(res); | 
|  |  | 
|  | pd->reg = ioremap(res->start, size); | 
|  | if (pd->reg == NULL) { | 
|  | dev_err(&dev->dev, "cannot map IO\n"); | 
|  | ret = -ENXIO; | 
|  | goto err_irq; | 
|  | } | 
|  |  | 
|  | /* Use platformd data bus speed or NORMAL_SPEED */ | 
|  | pd->bus_speed = NORMAL_SPEED; | 
|  | if (pdata && pdata->bus_speed) | 
|  | pd->bus_speed = pdata->bus_speed; | 
|  |  | 
|  | /* The IIC blocks on SH-Mobile ARM processors | 
|  | * come with two new bits in ICIC. | 
|  | */ | 
|  | if (size > 0x17) | 
|  | pd->flags |= IIC_FLAG_HAS_ICIC67; | 
|  |  | 
|  | /* Enable Runtime PM for this device. | 
|  | * | 
|  | * Also tell the Runtime PM core to ignore children | 
|  | * for this device since it is valid for us to suspend | 
|  | * this I2C master driver even though the slave devices | 
|  | * on the I2C bus may not be suspended. | 
|  | * | 
|  | * The state of the I2C hardware bus is unaffected by | 
|  | * the Runtime PM state. | 
|  | */ | 
|  | pm_suspend_ignore_children(&dev->dev, true); | 
|  | pm_runtime_enable(&dev->dev); | 
|  |  | 
|  | /* setup the private data */ | 
|  | adap = &pd->adap; | 
|  | i2c_set_adapdata(adap, pd); | 
|  |  | 
|  | adap->owner = THIS_MODULE; | 
|  | adap->algo = &sh_mobile_i2c_algorithm; | 
|  | adap->dev.parent = &dev->dev; | 
|  | adap->retries = 5; | 
|  | adap->nr = dev->id; | 
|  |  | 
|  | strlcpy(adap->name, dev->name, sizeof(adap->name)); | 
|  |  | 
|  | spin_lock_init(&pd->lock); | 
|  | init_waitqueue_head(&pd->wait); | 
|  |  | 
|  | ret = i2c_add_numbered_adapter(adap); | 
|  | if (ret < 0) { | 
|  | dev_err(&dev->dev, "cannot add numbered adapter\n"); | 
|  | goto err_all; | 
|  | } | 
|  |  | 
|  | dev_info(&dev->dev, "I2C adapter %d with bus speed %lu Hz\n", | 
|  | adap->nr, pd->bus_speed); | 
|  | return 0; | 
|  |  | 
|  | err_all: | 
|  | iounmap(pd->reg); | 
|  | err_irq: | 
|  | sh_mobile_i2c_hook_irqs(dev, 0); | 
|  | err_clk: | 
|  | clk_put(pd->clk); | 
|  | err: | 
|  | kfree(pd); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int sh_mobile_i2c_remove(struct platform_device *dev) | 
|  | { | 
|  | struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev); | 
|  |  | 
|  | i2c_del_adapter(&pd->adap); | 
|  | iounmap(pd->reg); | 
|  | sh_mobile_i2c_hook_irqs(dev, 0); | 
|  | clk_put(pd->clk); | 
|  | pm_runtime_disable(&dev->dev); | 
|  | kfree(pd); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int sh_mobile_i2c_runtime_nop(struct device *dev) | 
|  | { | 
|  | /* Runtime PM callback shared between ->runtime_suspend() | 
|  | * and ->runtime_resume(). Simply returns success. | 
|  | * | 
|  | * This driver re-initializes all registers after | 
|  | * pm_runtime_get_sync() anyway so there is no need | 
|  | * to save and restore registers here. | 
|  | */ | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static const struct dev_pm_ops sh_mobile_i2c_dev_pm_ops = { | 
|  | .runtime_suspend = sh_mobile_i2c_runtime_nop, | 
|  | .runtime_resume = sh_mobile_i2c_runtime_nop, | 
|  | }; | 
|  |  | 
|  | static struct platform_driver sh_mobile_i2c_driver = { | 
|  | .driver		= { | 
|  | .name		= "i2c-sh_mobile", | 
|  | .owner		= THIS_MODULE, | 
|  | .pm		= &sh_mobile_i2c_dev_pm_ops, | 
|  | }, | 
|  | .probe		= sh_mobile_i2c_probe, | 
|  | .remove		= sh_mobile_i2c_remove, | 
|  | }; | 
|  |  | 
|  | static int __init sh_mobile_i2c_adap_init(void) | 
|  | { | 
|  | return platform_driver_register(&sh_mobile_i2c_driver); | 
|  | } | 
|  |  | 
|  | static void __exit sh_mobile_i2c_adap_exit(void) | 
|  | { | 
|  | platform_driver_unregister(&sh_mobile_i2c_driver); | 
|  | } | 
|  |  | 
|  | subsys_initcall(sh_mobile_i2c_adap_init); | 
|  | module_exit(sh_mobile_i2c_adap_exit); | 
|  |  | 
|  | MODULE_DESCRIPTION("SuperH Mobile I2C Bus Controller driver"); | 
|  | MODULE_AUTHOR("Magnus Damm"); | 
|  | MODULE_LICENSE("GPL v2"); | 
|  | MODULE_ALIAS("platform:i2c-sh_mobile"); |