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alistair23-linux/drivers/i2c/busses/i2c-cpm.c

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 Based on 3 normalized pattern(s): 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 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 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 [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] 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 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 [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-27 00:55:06 -06:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Freescale CPM1/CPM2 I2C interface.
* Copyright (c) 1999 Dan Malek (dmalek@jlc.net).
*
* moved into proper i2c interface;
* Brad Parker (brad@heeltoe.com)
*
* Parts from dbox2_i2c.c (cvs.tuxbox.org)
* (C) 2000-2001 Felix Domke (tmbinc@gmx.net), Gillem (htoa@gmx.net)
*
* (C) 2007 Montavista Software, Inc.
* Vitaly Bordug <vitb@kernel.crashing.org>
*
* Converted to of_platform_device. Renamed to i2c-cpm.c.
* (C) 2007,2008 Jochen Friedrich <jochen@scram.de>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/stddef.h>
#include <linux/i2c.h>
#include <linux/io.h>
#include <linux/dma-mapping.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <sysdev/fsl_soc.h>
#include <asm/cpm.h>
/* Try to define this if you have an older CPU (earlier than rev D4) */
/* However, better use a GPIO based bitbang driver in this case :/ */
#undef I2C_CHIP_ERRATA
#define CPM_MAX_READ 513
#define CPM_MAXBD 4
#define I2C_EB (0x10) /* Big endian mode */
#define I2C_EB_CPM2 (0x30) /* Big endian mode, memory snoop */
#define DPRAM_BASE ((u8 __iomem __force *)cpm_muram_addr(0))
/* I2C parameter RAM. */
struct i2c_ram {
ushort rbase; /* Rx Buffer descriptor base address */
ushort tbase; /* Tx Buffer descriptor base address */
u_char rfcr; /* Rx function code */
u_char tfcr; /* Tx function code */
ushort mrblr; /* Max receive buffer length */
uint rstate; /* Internal */
uint rdp; /* Internal */
ushort rbptr; /* Rx Buffer descriptor pointer */
ushort rbc; /* Internal */
uint rxtmp; /* Internal */
uint tstate; /* Internal */
uint tdp; /* Internal */
ushort tbptr; /* Tx Buffer descriptor pointer */
ushort tbc; /* Internal */
uint txtmp; /* Internal */
char res1[4]; /* Reserved */
ushort rpbase; /* Relocation pointer */
char res2[2]; /* Reserved */
};
#define I2COM_START 0x80
#define I2COM_MASTER 0x01
#define I2CER_TXE 0x10
#define I2CER_BUSY 0x04
#define I2CER_TXB 0x02
#define I2CER_RXB 0x01
#define I2MOD_EN 0x01
/* I2C Registers */
struct i2c_reg {
u8 i2mod;
u8 res1[3];
u8 i2add;
u8 res2[3];
u8 i2brg;
u8 res3[3];
u8 i2com;
u8 res4[3];
u8 i2cer;
u8 res5[3];
u8 i2cmr;
};
struct cpm_i2c {
char *base;
struct platform_device *ofdev;
struct i2c_adapter adap;
uint dp_addr;
int version; /* CPM1=1, CPM2=2 */
int irq;
int cp_command;
int freq;
struct i2c_reg __iomem *i2c_reg;
struct i2c_ram __iomem *i2c_ram;
u16 i2c_addr;
wait_queue_head_t i2c_wait;
cbd_t __iomem *tbase;
cbd_t __iomem *rbase;
u_char *txbuf[CPM_MAXBD];
u_char *rxbuf[CPM_MAXBD];
dma_addr_t txdma[CPM_MAXBD];
dma_addr_t rxdma[CPM_MAXBD];
};
static irqreturn_t cpm_i2c_interrupt(int irq, void *dev_id)
{
struct cpm_i2c *cpm;
struct i2c_reg __iomem *i2c_reg;
struct i2c_adapter *adap = dev_id;
int i;
cpm = i2c_get_adapdata(dev_id);
i2c_reg = cpm->i2c_reg;
/* Clear interrupt. */
i = in_8(&i2c_reg->i2cer);
out_8(&i2c_reg->i2cer, i);
dev_dbg(&adap->dev, "Interrupt: %x\n", i);
i2c: Fix stuck transaction on cpm-i2c driver When a process tries to read/write a disconnected i2c device, it receives a signal (e.g. ctrl-c) and the kernel gets stuck. BUG: soft lockup - CPU#0 stuck for 61s! [I2CEEpromTest:392] NIP: c01628f8 LR: c01628f0 CTR: c00177cc REGS: c39abd70 TRAP: 0901 Not tainted (2.6.25.7-alcore) MSR: 00009032 <EE,ME,IR,DR> CR: 42042048 XER: 20000000 TASK = c3889bd0[392] 'I2CEEpromTest' THREAD: c39aa000 GPR00: 00009000 c39abe20 c3889bd0 c39075c8 c39abe28 00000001 00000000 00000001 GPR08: c3889bd0 c39075c8 00009032 c39abe34 00002437 NIP [c01628f8] cpm_i2c_xfer+0x5fc/0x6d0 LR [c01628f0] cpm_i2c_xfer+0x5f4/0x6d0 Call Trace: [c39abe20] [c0162924] cpm_i2c_xfer+0x628/0x6d0 (unreliable) [c39abe90] [c015f6a0] i2c_transfer+0x88/0xb4 [c39abeb0] [c0160164] i2c_master_recv+0x48/0x6c [c39abed0] [c01618dc] i2cdev_read+0x50/0xe4 [c39abef0] [c0068b24] vfs_read+0xc4/0x108 [c39abf10] [c0068f4c] sys_read+0x4c/0x90 [c39abf40] [c000d348] ret_from_syscall+0x0/0x38 Instruction dump: 3bc00064 92610010 3bf201c8 92810014 3b61 This happen because though the wait_event_interruptible_timeout takes the signals into account, the driver does not handle them. We propose to change the wait_event_interruptible_timeout with wait_event_timeout, leaving the signals to be handled in other points on the upper layers. Signed-off-by: Bruno Morelli <bruno@evidence.eu.com> Signed-off-by: Michael Trimarchi <michael@evidence.eu.com> Acked-by: Jochen Friedrich <jochen@scram.de> [ben-linux@fluff.org: fix title for patch] Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-19 06:50:02 -06:00
wake_up(&cpm->i2c_wait);
return i ? IRQ_HANDLED : IRQ_NONE;
}
static void cpm_reset_i2c_params(struct cpm_i2c *cpm)
{
struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram;
/* Set up the I2C parameters in the parameter ram. */
out_be16(&i2c_ram->tbase, (u8 __iomem *)cpm->tbase - DPRAM_BASE);
out_be16(&i2c_ram->rbase, (u8 __iomem *)cpm->rbase - DPRAM_BASE);
if (cpm->version == 1) {
out_8(&i2c_ram->tfcr, I2C_EB);
out_8(&i2c_ram->rfcr, I2C_EB);
} else {
out_8(&i2c_ram->tfcr, I2C_EB_CPM2);
out_8(&i2c_ram->rfcr, I2C_EB_CPM2);
}
out_be16(&i2c_ram->mrblr, CPM_MAX_READ);
out_be32(&i2c_ram->rstate, 0);
out_be32(&i2c_ram->rdp, 0);
out_be16(&i2c_ram->rbptr, 0);
out_be16(&i2c_ram->rbc, 0);
out_be32(&i2c_ram->rxtmp, 0);
out_be32(&i2c_ram->tstate, 0);
out_be32(&i2c_ram->tdp, 0);
out_be16(&i2c_ram->tbptr, 0);
out_be16(&i2c_ram->tbc, 0);
out_be32(&i2c_ram->txtmp, 0);
}
static void cpm_i2c_force_close(struct i2c_adapter *adap)
{
struct cpm_i2c *cpm = i2c_get_adapdata(adap);
struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg;
dev_dbg(&adap->dev, "cpm_i2c_force_close()\n");
cpm_command(cpm->cp_command, CPM_CR_CLOSE_RX_BD);
out_8(&i2c_reg->i2cmr, 0x00); /* Disable all interrupts */
out_8(&i2c_reg->i2cer, 0xff);
}
static void cpm_i2c_parse_message(struct i2c_adapter *adap,
struct i2c_msg *pmsg, int num, int tx, int rx)
{
cbd_t __iomem *tbdf;
cbd_t __iomem *rbdf;
u_char addr;
u_char *tb;
u_char *rb;
struct cpm_i2c *cpm = i2c_get_adapdata(adap);
tbdf = cpm->tbase + tx;
rbdf = cpm->rbase + rx;
addr = i2c_8bit_addr_from_msg(pmsg);
tb = cpm->txbuf[tx];
rb = cpm->rxbuf[rx];
/* Align read buffer */
rb = (u_char *) (((ulong) rb + 1) & ~1);
tb[0] = addr; /* Device address byte w/rw flag */
out_be16(&tbdf->cbd_datlen, pmsg->len + 1);
out_be16(&tbdf->cbd_sc, 0);
if (!(pmsg->flags & I2C_M_NOSTART))
setbits16(&tbdf->cbd_sc, BD_I2C_START);
if (tx + 1 == num)
setbits16(&tbdf->cbd_sc, BD_SC_LAST | BD_SC_WRAP);
if (pmsg->flags & I2C_M_RD) {
/*
* To read, we need an empty buffer of the proper length.
* All that is used is the first byte for address, the remainder
* is just used for timing (and doesn't really have to exist).
*/
dev_dbg(&adap->dev, "cpm_i2c_read(abyte=0x%x)\n", addr);
out_be16(&rbdf->cbd_datlen, 0);
out_be16(&rbdf->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT);
if (rx + 1 == CPM_MAXBD)
setbits16(&rbdf->cbd_sc, BD_SC_WRAP);
eieio();
setbits16(&tbdf->cbd_sc, BD_SC_READY);
} else {
dev_dbg(&adap->dev, "cpm_i2c_write(abyte=0x%x)\n", addr);
memcpy(tb+1, pmsg->buf, pmsg->len);
eieio();
setbits16(&tbdf->cbd_sc, BD_SC_READY | BD_SC_INTRPT);
}
}
static int cpm_i2c_check_message(struct i2c_adapter *adap,
struct i2c_msg *pmsg, int tx, int rx)
{
cbd_t __iomem *tbdf;
cbd_t __iomem *rbdf;
u_char *tb;
u_char *rb;
struct cpm_i2c *cpm = i2c_get_adapdata(adap);
tbdf = cpm->tbase + tx;
rbdf = cpm->rbase + rx;
tb = cpm->txbuf[tx];
rb = cpm->rxbuf[rx];
/* Align read buffer */
rb = (u_char *) (((uint) rb + 1) & ~1);
eieio();
if (pmsg->flags & I2C_M_RD) {
dev_dbg(&adap->dev, "tx sc 0x%04x, rx sc 0x%04x\n",
in_be16(&tbdf->cbd_sc), in_be16(&rbdf->cbd_sc));
if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) {
dev_dbg(&adap->dev, "I2C read; No ack\n");
return -ENXIO;
}
if (in_be16(&rbdf->cbd_sc) & BD_SC_EMPTY) {
dev_err(&adap->dev,
"I2C read; complete but rbuf empty\n");
return -EREMOTEIO;
}
if (in_be16(&rbdf->cbd_sc) & BD_SC_OV) {
dev_err(&adap->dev, "I2C read; Overrun\n");
return -EREMOTEIO;
}
memcpy(pmsg->buf, rb, pmsg->len);
} else {
dev_dbg(&adap->dev, "tx sc %d 0x%04x\n", tx,
in_be16(&tbdf->cbd_sc));
if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) {
dev_dbg(&adap->dev, "I2C write; No ack\n");
return -ENXIO;
}
if (in_be16(&tbdf->cbd_sc) & BD_SC_UN) {
dev_err(&adap->dev, "I2C write; Underrun\n");
return -EIO;
}
if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) {
dev_err(&adap->dev, "I2C write; Collision\n");
return -EIO;
}
}
return 0;
}
static int cpm_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
struct cpm_i2c *cpm = i2c_get_adapdata(adap);
struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg;
struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram;
struct i2c_msg *pmsg;
int ret;
int tptr;
int rptr;
cbd_t __iomem *tbdf;
cbd_t __iomem *rbdf;
/* Reset to use first buffer */
out_be16(&i2c_ram->rbptr, in_be16(&i2c_ram->rbase));
out_be16(&i2c_ram->tbptr, in_be16(&i2c_ram->tbase));
tbdf = cpm->tbase;
rbdf = cpm->rbase;
tptr = 0;
rptr = 0;
/*
* If there was a collision in the last i2c transaction,
* Set I2COM_MASTER as it was cleared during collision.
*/
if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) {
out_8(&cpm->i2c_reg->i2com, I2COM_MASTER);
}
while (tptr < num) {
pmsg = &msgs[tptr];
dev_dbg(&adap->dev, "R: %d T: %d\n", rptr, tptr);
cpm_i2c_parse_message(adap, pmsg, num, tptr, rptr);
if (pmsg->flags & I2C_M_RD)
rptr++;
tptr++;
}
/* Start transfer now */
/* Enable RX/TX/Error interupts */
out_8(&i2c_reg->i2cmr, I2CER_TXE | I2CER_TXB | I2CER_RXB);
out_8(&i2c_reg->i2cer, 0xff); /* Clear interrupt status */
/* Chip bug, set enable here */
setbits8(&i2c_reg->i2mod, I2MOD_EN); /* Enable */
/* Begin transmission */
setbits8(&i2c_reg->i2com, I2COM_START);
tptr = 0;
rptr = 0;
while (tptr < num) {
/* Check for outstanding messages */
dev_dbg(&adap->dev, "test ready.\n");
pmsg = &msgs[tptr];
if (pmsg->flags & I2C_M_RD)
i2c: Fix stuck transaction on cpm-i2c driver When a process tries to read/write a disconnected i2c device, it receives a signal (e.g. ctrl-c) and the kernel gets stuck. BUG: soft lockup - CPU#0 stuck for 61s! [I2CEEpromTest:392] NIP: c01628f8 LR: c01628f0 CTR: c00177cc REGS: c39abd70 TRAP: 0901 Not tainted (2.6.25.7-alcore) MSR: 00009032 <EE,ME,IR,DR> CR: 42042048 XER: 20000000 TASK = c3889bd0[392] 'I2CEEpromTest' THREAD: c39aa000 GPR00: 00009000 c39abe20 c3889bd0 c39075c8 c39abe28 00000001 00000000 00000001 GPR08: c3889bd0 c39075c8 00009032 c39abe34 00002437 NIP [c01628f8] cpm_i2c_xfer+0x5fc/0x6d0 LR [c01628f0] cpm_i2c_xfer+0x5f4/0x6d0 Call Trace: [c39abe20] [c0162924] cpm_i2c_xfer+0x628/0x6d0 (unreliable) [c39abe90] [c015f6a0] i2c_transfer+0x88/0xb4 [c39abeb0] [c0160164] i2c_master_recv+0x48/0x6c [c39abed0] [c01618dc] i2cdev_read+0x50/0xe4 [c39abef0] [c0068b24] vfs_read+0xc4/0x108 [c39abf10] [c0068f4c] sys_read+0x4c/0x90 [c39abf40] [c000d348] ret_from_syscall+0x0/0x38 Instruction dump: 3bc00064 92610010 3bf201c8 92810014 3b61 This happen because though the wait_event_interruptible_timeout takes the signals into account, the driver does not handle them. We propose to change the wait_event_interruptible_timeout with wait_event_timeout, leaving the signals to be handled in other points on the upper layers. Signed-off-by: Bruno Morelli <bruno@evidence.eu.com> Signed-off-by: Michael Trimarchi <michael@evidence.eu.com> Acked-by: Jochen Friedrich <jochen@scram.de> [ben-linux@fluff.org: fix title for patch] Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-19 06:50:02 -06:00
ret = wait_event_timeout(cpm->i2c_wait,
(in_be16(&tbdf[tptr].cbd_sc) & BD_SC_NAK) ||
!(in_be16(&rbdf[rptr].cbd_sc) & BD_SC_EMPTY),
1 * HZ);
else
i2c: Fix stuck transaction on cpm-i2c driver When a process tries to read/write a disconnected i2c device, it receives a signal (e.g. ctrl-c) and the kernel gets stuck. BUG: soft lockup - CPU#0 stuck for 61s! [I2CEEpromTest:392] NIP: c01628f8 LR: c01628f0 CTR: c00177cc REGS: c39abd70 TRAP: 0901 Not tainted (2.6.25.7-alcore) MSR: 00009032 <EE,ME,IR,DR> CR: 42042048 XER: 20000000 TASK = c3889bd0[392] 'I2CEEpromTest' THREAD: c39aa000 GPR00: 00009000 c39abe20 c3889bd0 c39075c8 c39abe28 00000001 00000000 00000001 GPR08: c3889bd0 c39075c8 00009032 c39abe34 00002437 NIP [c01628f8] cpm_i2c_xfer+0x5fc/0x6d0 LR [c01628f0] cpm_i2c_xfer+0x5f4/0x6d0 Call Trace: [c39abe20] [c0162924] cpm_i2c_xfer+0x628/0x6d0 (unreliable) [c39abe90] [c015f6a0] i2c_transfer+0x88/0xb4 [c39abeb0] [c0160164] i2c_master_recv+0x48/0x6c [c39abed0] [c01618dc] i2cdev_read+0x50/0xe4 [c39abef0] [c0068b24] vfs_read+0xc4/0x108 [c39abf10] [c0068f4c] sys_read+0x4c/0x90 [c39abf40] [c000d348] ret_from_syscall+0x0/0x38 Instruction dump: 3bc00064 92610010 3bf201c8 92810014 3b61 This happen because though the wait_event_interruptible_timeout takes the signals into account, the driver does not handle them. We propose to change the wait_event_interruptible_timeout with wait_event_timeout, leaving the signals to be handled in other points on the upper layers. Signed-off-by: Bruno Morelli <bruno@evidence.eu.com> Signed-off-by: Michael Trimarchi <michael@evidence.eu.com> Acked-by: Jochen Friedrich <jochen@scram.de> [ben-linux@fluff.org: fix title for patch] Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-06-19 06:50:02 -06:00
ret = wait_event_timeout(cpm->i2c_wait,
!(in_be16(&tbdf[tptr].cbd_sc) & BD_SC_READY),
1 * HZ);
if (ret == 0) {
ret = -EREMOTEIO;
dev_err(&adap->dev, "I2C transfer: timeout\n");
goto out_err;
}
if (ret > 0) {
dev_dbg(&adap->dev, "ready.\n");
ret = cpm_i2c_check_message(adap, pmsg, tptr, rptr);
tptr++;
if (pmsg->flags & I2C_M_RD)
rptr++;
if (ret)
goto out_err;
}
}
#ifdef I2C_CHIP_ERRATA
/*
* Chip errata, clear enable. This is not needed on rev D4 CPUs.
* Disabling I2C too early may cause too short stop condition
*/
udelay(4);
clrbits8(&i2c_reg->i2mod, I2MOD_EN);
#endif
return (num);
out_err:
cpm_i2c_force_close(adap);
#ifdef I2C_CHIP_ERRATA
/*
* Chip errata, clear enable. This is not needed on rev D4 CPUs.
*/
clrbits8(&i2c_reg->i2mod, I2MOD_EN);
#endif
return ret;
}
static u32 cpm_i2c_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
}
/* -----exported algorithm data: ------------------------------------- */
static const struct i2c_algorithm cpm_i2c_algo = {
.master_xfer = cpm_i2c_xfer,
.functionality = cpm_i2c_func,
};
/* CPM_MAX_READ is also limiting writes according to the code! */
static const struct i2c_adapter_quirks cpm_i2c_quirks = {
.max_num_msgs = CPM_MAXBD,
.max_read_len = CPM_MAX_READ,
.max_write_len = CPM_MAX_READ,
};
static const struct i2c_adapter cpm_ops = {
.owner = THIS_MODULE,
.name = "i2c-cpm",
.algo = &cpm_i2c_algo,
.quirks = &cpm_i2c_quirks,
};
static int cpm_i2c_setup(struct cpm_i2c *cpm)
{
struct platform_device *ofdev = cpm->ofdev;
const u32 *data;
int len, ret, i;
void __iomem *i2c_base;
cbd_t __iomem *tbdf;
cbd_t __iomem *rbdf;
unsigned char brg;
dev_dbg(&cpm->ofdev->dev, "cpm_i2c_setup()\n");
init_waitqueue_head(&cpm->i2c_wait);
cpm->irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
if (!cpm->irq)
return -EINVAL;
/* Install interrupt handler. */
ret = request_irq(cpm->irq, cpm_i2c_interrupt, 0, "cpm_i2c",
&cpm->adap);
if (ret)
return ret;
/* I2C parameter RAM */
i2c_base = of_iomap(ofdev->dev.of_node, 1);
if (i2c_base == NULL) {
ret = -EINVAL;
goto out_irq;
}
if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm1-i2c")) {
/* Check for and use a microcode relocation patch. */
cpm->i2c_ram = i2c_base;
cpm->i2c_addr = in_be16(&cpm->i2c_ram->rpbase);
/*
* Maybe should use cpm_muram_alloc instead of hardcoding
* this in micropatch.c
*/
if (cpm->i2c_addr) {
cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr);
iounmap(i2c_base);
}
cpm->version = 1;
} else if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm2-i2c")) {
cpm->i2c_addr = cpm_muram_alloc(sizeof(struct i2c_ram), 64);
cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr);
out_be16(i2c_base, cpm->i2c_addr);
iounmap(i2c_base);
cpm->version = 2;
} else {
iounmap(i2c_base);
ret = -EINVAL;
goto out_irq;
}
/* I2C control/status registers */
cpm->i2c_reg = of_iomap(ofdev->dev.of_node, 0);
if (cpm->i2c_reg == NULL) {
ret = -EINVAL;
goto out_ram;
}
data = of_get_property(ofdev->dev.of_node, "fsl,cpm-command", &len);
if (!data || len != 4) {
ret = -EINVAL;
goto out_reg;
}
cpm->cp_command = *data;
data = of_get_property(ofdev->dev.of_node, "linux,i2c-class", &len);
if (data && len == 4)
cpm->adap.class = *data;
data = of_get_property(ofdev->dev.of_node, "clock-frequency", &len);
if (data && len == 4)
cpm->freq = *data;
else
cpm->freq = 60000; /* use 60kHz i2c clock by default */
/*
* Allocate space for CPM_MAXBD transmit and receive buffer
* descriptors in the DP ram.
*/
cpm->dp_addr = cpm_muram_alloc(sizeof(cbd_t) * 2 * CPM_MAXBD, 8);
if (!cpm->dp_addr) {
ret = -ENOMEM;
goto out_reg;
}
cpm->tbase = cpm_muram_addr(cpm->dp_addr);
cpm->rbase = cpm_muram_addr(cpm->dp_addr + sizeof(cbd_t) * CPM_MAXBD);
/* Allocate TX and RX buffers */
tbdf = cpm->tbase;
rbdf = cpm->rbase;
for (i = 0; i < CPM_MAXBD; i++) {
cpm->rxbuf[i] = dma_alloc_coherent(&cpm->ofdev->dev,
CPM_MAX_READ + 1,
&cpm->rxdma[i], GFP_KERNEL);
if (!cpm->rxbuf[i]) {
ret = -ENOMEM;
goto out_muram;
}
out_be32(&rbdf[i].cbd_bufaddr, ((cpm->rxdma[i] + 1) & ~1));
cpm->txbuf[i] = dma_alloc_coherent(&cpm->ofdev->dev,
CPM_MAX_READ + 1,
&cpm->txdma[i], GFP_KERNEL);
if (!cpm->txbuf[i]) {
ret = -ENOMEM;
goto out_muram;
}
out_be32(&tbdf[i].cbd_bufaddr, cpm->txdma[i]);
}
/* Initialize Tx/Rx parameters. */
cpm_reset_i2c_params(cpm);
dev_dbg(&cpm->ofdev->dev, "i2c_ram 0x%p, i2c_addr 0x%04x, freq %d\n",
cpm->i2c_ram, cpm->i2c_addr, cpm->freq);
dev_dbg(&cpm->ofdev->dev, "tbase 0x%04x, rbase 0x%04x\n",
(u8 __iomem *)cpm->tbase - DPRAM_BASE,
(u8 __iomem *)cpm->rbase - DPRAM_BASE);
cpm_command(cpm->cp_command, CPM_CR_INIT_TRX);
/*
* Select an invalid address. Just make sure we don't use loopback mode
*/
out_8(&cpm->i2c_reg->i2add, 0x7f << 1);
/*
* PDIV is set to 00 in i2mod, so brgclk/32 is used as input to the
* i2c baud rate generator. This is divided by 2 x (DIV + 3) to get
* the actual i2c bus frequency.
*/
brg = get_brgfreq() / (32 * 2 * cpm->freq) - 3;
out_8(&cpm->i2c_reg->i2brg, brg);
out_8(&cpm->i2c_reg->i2mod, 0x00);
out_8(&cpm->i2c_reg->i2com, I2COM_MASTER); /* Master mode */
/* Disable interrupts. */
out_8(&cpm->i2c_reg->i2cmr, 0);
out_8(&cpm->i2c_reg->i2cer, 0xff);
return 0;
out_muram:
for (i = 0; i < CPM_MAXBD; i++) {
if (cpm->rxbuf[i])
dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
cpm->rxbuf[i], cpm->rxdma[i]);
if (cpm->txbuf[i])
dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
cpm->txbuf[i], cpm->txdma[i]);
}
cpm_muram_free(cpm->dp_addr);
out_reg:
iounmap(cpm->i2c_reg);
out_ram:
if ((cpm->version == 1) && (!cpm->i2c_addr))
iounmap(cpm->i2c_ram);
if (cpm->version == 2)
cpm_muram_free(cpm->i2c_addr);
out_irq:
free_irq(cpm->irq, &cpm->adap);
return ret;
}
static void cpm_i2c_shutdown(struct cpm_i2c *cpm)
{
int i;
/* Shut down I2C. */
clrbits8(&cpm->i2c_reg->i2mod, I2MOD_EN);
/* Disable interrupts */
out_8(&cpm->i2c_reg->i2cmr, 0);
out_8(&cpm->i2c_reg->i2cer, 0xff);
free_irq(cpm->irq, &cpm->adap);
/* Free all memory */
for (i = 0; i < CPM_MAXBD; i++) {
dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
cpm->rxbuf[i], cpm->rxdma[i]);
dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
cpm->txbuf[i], cpm->txdma[i]);
}
cpm_muram_free(cpm->dp_addr);
iounmap(cpm->i2c_reg);
if ((cpm->version == 1) && (!cpm->i2c_addr))
iounmap(cpm->i2c_ram);
if (cpm->version == 2)
cpm_muram_free(cpm->i2c_addr);
}
static int cpm_i2c_probe(struct platform_device *ofdev)
{
int result, len;
struct cpm_i2c *cpm;
const u32 *data;
cpm = kzalloc(sizeof(struct cpm_i2c), GFP_KERNEL);
if (!cpm)
return -ENOMEM;
cpm->ofdev = ofdev;
platform_set_drvdata(ofdev, cpm);
cpm->adap = cpm_ops;
i2c_set_adapdata(&cpm->adap, cpm);
cpm->adap.dev.parent = &ofdev->dev;
cpm->adap.dev.of_node = of_node_get(ofdev->dev.of_node);
result = cpm_i2c_setup(cpm);
if (result) {
dev_err(&ofdev->dev, "Unable to init hardware\n");
goto out_free;
}
/* register new adapter to i2c module... */
data = of_get_property(ofdev->dev.of_node, "linux,i2c-index", &len);
cpm->adap.nr = (data && len == 4) ? be32_to_cpup(data) : -1;
result = i2c_add_numbered_adapter(&cpm->adap);
if (result < 0)
goto out_shut;
dev_dbg(&ofdev->dev, "hw routines for %s registered.\n",
cpm->adap.name);
return 0;
out_shut:
cpm_i2c_shutdown(cpm);
out_free:
kfree(cpm);
return result;
}
static int cpm_i2c_remove(struct platform_device *ofdev)
{
struct cpm_i2c *cpm = platform_get_drvdata(ofdev);
i2c_del_adapter(&cpm->adap);
cpm_i2c_shutdown(cpm);
kfree(cpm);
return 0;
}
static const struct of_device_id cpm_i2c_match[] = {
{
.compatible = "fsl,cpm1-i2c",
},
{
.compatible = "fsl,cpm2-i2c",
},
{},
};
MODULE_DEVICE_TABLE(of, cpm_i2c_match);
static struct platform_driver cpm_i2c_driver = {
.probe = cpm_i2c_probe,
.remove = cpm_i2c_remove,
.driver = {
.name = "fsl-i2c-cpm",
.of_match_table = cpm_i2c_match,
},
};
module_platform_driver(cpm_i2c_driver);
MODULE_AUTHOR("Jochen Friedrich <jochen@scram.de>");
MODULE_DESCRIPTION("I2C-Bus adapter routines for CPM boards");
MODULE_LICENSE("GPL");