linux/drivers/i2c/busses/i2c-omap.c

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/*
* TI OMAP I2C master mode driver
*
* Copyright (C) 2003 MontaVista Software, Inc.
* Copyright (C) 2005 Nokia Corporation
* Copyright (C) 2004 - 2007 Texas Instruments.
*
* Originally written by MontaVista Software, Inc.
* Additional contributions by:
* Tony Lindgren <tony@atomide.com>
* Imre Deak <imre.deak@nokia.com>
* Juha Yrjölä <juha.yrjola@solidboot.com>
* Syed Khasim <x0khasim@ti.com>
* Nishant Menon <nm@ti.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, 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.
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/completion.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_i2c.h>
#include <linux/of_device.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/i2c-omap.h>
#include <linux/pm_runtime.h>
#include <linux/pinctrl/consumer.h>
/* I2C controller revisions */
#define OMAP_I2C_OMAP1_REV_2 0x20
/* I2C controller revisions present on specific hardware */
#define OMAP_I2C_REV_ON_2430 0x00000036
#define OMAP_I2C_REV_ON_3430_3530 0x0000003C
#define OMAP_I2C_REV_ON_3630 0x00000040
#define OMAP_I2C_REV_ON_4430_PLUS 0x50400002
/* timeout waiting for the controller to respond */
#define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
/* timeout for pm runtime autosuspend */
#define OMAP_I2C_PM_TIMEOUT 1000 /* ms */
/* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
enum {
OMAP_I2C_REV_REG = 0,
OMAP_I2C_IE_REG,
OMAP_I2C_STAT_REG,
OMAP_I2C_IV_REG,
OMAP_I2C_WE_REG,
OMAP_I2C_SYSS_REG,
OMAP_I2C_BUF_REG,
OMAP_I2C_CNT_REG,
OMAP_I2C_DATA_REG,
OMAP_I2C_SYSC_REG,
OMAP_I2C_CON_REG,
OMAP_I2C_OA_REG,
OMAP_I2C_SA_REG,
OMAP_I2C_PSC_REG,
OMAP_I2C_SCLL_REG,
OMAP_I2C_SCLH_REG,
OMAP_I2C_SYSTEST_REG,
OMAP_I2C_BUFSTAT_REG,
/* only on OMAP4430 */
OMAP_I2C_IP_V2_REVNB_LO,
OMAP_I2C_IP_V2_REVNB_HI,
OMAP_I2C_IP_V2_IRQSTATUS_RAW,
OMAP_I2C_IP_V2_IRQENABLE_SET,
OMAP_I2C_IP_V2_IRQENABLE_CLR,
};
/* I2C Interrupt Enable Register (OMAP_I2C_IE): */
#define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer drain int enable */
#define OMAP_I2C_IE_RDR (1 << 13) /* RX Buffer drain int enable */
#define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */
#define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */
#define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */
#define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */
#define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */
/* I2C Status Register (OMAP_I2C_STAT): */
#define OMAP_I2C_STAT_XDR (1 << 14) /* TX Buffer draining */
#define OMAP_I2C_STAT_RDR (1 << 13) /* RX Buffer draining */
#define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */
#define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */
#define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */
#define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */
#define OMAP_I2C_STAT_AD0 (1 << 8) /* Address zero */
#define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */
#define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */
#define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */
#define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */
#define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */
/* I2C WE wakeup enable register */
#define OMAP_I2C_WE_XDR_WE (1 << 14) /* TX drain wakup */
#define OMAP_I2C_WE_RDR_WE (1 << 13) /* RX drain wakeup */
#define OMAP_I2C_WE_AAS_WE (1 << 9) /* Address as slave wakeup*/
#define OMAP_I2C_WE_BF_WE (1 << 8) /* Bus free wakeup */
#define OMAP_I2C_WE_STC_WE (1 << 6) /* Start condition wakeup */
#define OMAP_I2C_WE_GC_WE (1 << 5) /* General call wakeup */
#define OMAP_I2C_WE_DRDY_WE (1 << 3) /* TX/RX data ready wakeup */
#define OMAP_I2C_WE_ARDY_WE (1 << 2) /* Reg access ready wakeup */
#define OMAP_I2C_WE_NACK_WE (1 << 1) /* No acknowledgment wakeup */
#define OMAP_I2C_WE_AL_WE (1 << 0) /* Arbitration lost wakeup */
#define OMAP_I2C_WE_ALL (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
/* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
#define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */
#define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */
#define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */
#define OMAP_I2C_BUF_TXFIF_CLR (1 << 6) /* TX FIFO Clear */
/* I2C Configuration Register (OMAP_I2C_CON): */
#define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */
#define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */
#define OMAP_I2C_CON_OPMODE_HS (1 << 12) /* High Speed support */
#define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */
#define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */
#define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */
#define OMAP_I2C_CON_XA (1 << 8) /* Expand address */
#define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */
#define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */
#define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */
/* I2C SCL time value when Master */
#define OMAP_I2C_SCLL_HSSCLL 8
#define OMAP_I2C_SCLH_HSSCLH 8
/* I2C System Test Register (OMAP_I2C_SYSTEST): */
#ifdef DEBUG
#define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */
#define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */
#define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */
#define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */
#define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */
#define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */
#define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */
#define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */
#endif
/* OCP_SYSSTATUS bit definitions */
#define SYSS_RESETDONE_MASK (1 << 0)
/* OCP_SYSCONFIG bit definitions */
#define SYSC_CLOCKACTIVITY_MASK (0x3 << 8)
#define SYSC_SIDLEMODE_MASK (0x3 << 3)
#define SYSC_ENAWAKEUP_MASK (1 << 2)
#define SYSC_SOFTRESET_MASK (1 << 1)
#define SYSC_AUTOIDLE_MASK (1 << 0)
#define SYSC_IDLEMODE_SMART 0x2
#define SYSC_CLOCKACTIVITY_FCLK 0x2
/* Errata definitions */
#define I2C_OMAP_ERRATA_I207 (1 << 0)
#define I2C_OMAP_ERRATA_I462 (1 << 1)
struct omap_i2c_dev {
spinlock_t lock; /* IRQ synchronization */
struct device *dev;
void __iomem *base; /* virtual */
int irq;
int reg_shift; /* bit shift for I2C register addresses */
struct completion cmd_complete;
struct resource *ioarea;
u32 latency; /* maximum mpu wkup latency */
void (*set_mpu_wkup_lat)(struct device *dev,
long latency);
u32 speed; /* Speed of bus in kHz */
u32 flags;
u16 cmd_err;
u8 *buf;
u8 *regs;
size_t buf_len;
struct i2c_adapter adapter;
u8 threshold;
u8 fifo_size; /* use as flag and value
* fifo_size==0 implies no fifo
* if set, should be trsh+1
*/
u32 rev;
unsigned b_hw:1; /* bad h/w fixes */
unsigned receiver:1; /* true when we're in receiver mode */
u16 iestate; /* Saved interrupt register */
u16 pscstate;
u16 scllstate;
u16 sclhstate;
u16 syscstate;
u16 westate;
u16 errata;
struct pinctrl *pins;
};
static const u8 reg_map_ip_v1[] = {
[OMAP_I2C_REV_REG] = 0x00,
[OMAP_I2C_IE_REG] = 0x01,
[OMAP_I2C_STAT_REG] = 0x02,
[OMAP_I2C_IV_REG] = 0x03,
[OMAP_I2C_WE_REG] = 0x03,
[OMAP_I2C_SYSS_REG] = 0x04,
[OMAP_I2C_BUF_REG] = 0x05,
[OMAP_I2C_CNT_REG] = 0x06,
[OMAP_I2C_DATA_REG] = 0x07,
[OMAP_I2C_SYSC_REG] = 0x08,
[OMAP_I2C_CON_REG] = 0x09,
[OMAP_I2C_OA_REG] = 0x0a,
[OMAP_I2C_SA_REG] = 0x0b,
[OMAP_I2C_PSC_REG] = 0x0c,
[OMAP_I2C_SCLL_REG] = 0x0d,
[OMAP_I2C_SCLH_REG] = 0x0e,
[OMAP_I2C_SYSTEST_REG] = 0x0f,
[OMAP_I2C_BUFSTAT_REG] = 0x10,
};
static const u8 reg_map_ip_v2[] = {
[OMAP_I2C_REV_REG] = 0x04,
[OMAP_I2C_IE_REG] = 0x2c,
[OMAP_I2C_STAT_REG] = 0x28,
[OMAP_I2C_IV_REG] = 0x34,
[OMAP_I2C_WE_REG] = 0x34,
[OMAP_I2C_SYSS_REG] = 0x90,
[OMAP_I2C_BUF_REG] = 0x94,
[OMAP_I2C_CNT_REG] = 0x98,
[OMAP_I2C_DATA_REG] = 0x9c,
[OMAP_I2C_SYSC_REG] = 0x10,
[OMAP_I2C_CON_REG] = 0xa4,
[OMAP_I2C_OA_REG] = 0xa8,
[OMAP_I2C_SA_REG] = 0xac,
[OMAP_I2C_PSC_REG] = 0xb0,
[OMAP_I2C_SCLL_REG] = 0xb4,
[OMAP_I2C_SCLH_REG] = 0xb8,
[OMAP_I2C_SYSTEST_REG] = 0xbC,
[OMAP_I2C_BUFSTAT_REG] = 0xc0,
[OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
[OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
[OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
[OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
[OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
};
static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
int reg, u16 val)
{
__raw_writew(val, i2c_dev->base +
(i2c_dev->regs[reg] << i2c_dev->reg_shift));
}
static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
{
return __raw_readw(i2c_dev->base +
(i2c_dev->regs[reg] << i2c_dev->reg_shift));
}
static void __omap_i2c_init(struct omap_i2c_dev *dev)
{
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
/* SCL low and high time values */
omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
/* Take the I2C module out of reset: */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
/*
* Don't write to this register if the IE state is 0 as it can
* cause deadlock.
*/
if (dev->iestate)
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
}
static int omap_i2c_reset(struct omap_i2c_dev *dev)
{
unsigned long timeout;
u16 sysc;
if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG);
/* Disable I2C controller before soft reset */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
~(OMAP_I2C_CON_EN));
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
/* For some reason we need to set the EN bit before the
* reset done bit gets set. */
timeout = jiffies + OMAP_I2C_TIMEOUT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
SYSS_RESETDONE_MASK)) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting "
"for controller reset\n");
return -ETIMEDOUT;
}
msleep(1);
}
/* SYSC register is cleared by the reset; rewrite it */
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc);
}
return 0;
}
static int omap_i2c_init(struct omap_i2c_dev *dev)
{
u16 psc = 0, scll = 0, sclh = 0;
u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
unsigned long fclk_rate = 12000000;
unsigned long internal_clk = 0;
struct clk *fclk;
if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
/*
* Enabling all wakup sources to stop I2C freezing on
* WFI instruction.
* REVISIT: Some wkup sources might not be needed.
*/
dev->westate = OMAP_I2C_WE_ALL;
}
if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
/*
* The I2C functional clock is the armxor_ck, so there's
* no need to get "armxor_ck" separately. Now, if OMAP2420
* always returns 12MHz for the functional clock, we can
* do this bit unconditionally.
*/
fclk = clk_get(dev->dev, "fck");
fclk_rate = clk_get_rate(fclk);
clk_put(fclk);
/* TRM for 5912 says the I2C clock must be prescaled to be
* between 7 - 12 MHz. The XOR input clock is typically
* 12, 13 or 19.2 MHz. So we should have code that produces:
*
* XOR MHz Divider Prescaler
* 12 1 0
* 13 2 1
* 19.2 2 1
*/
if (fclk_rate > 12000000)
psc = fclk_rate / 12000000;
}
if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
/*
* HSI2C controller internal clk rate should be 19.2 Mhz for
* HS and for all modes on 2430. On 34xx we can use lower rate
* to get longer filter period for better noise suppression.
* The filter is iclk (fclk for HS) period.
*/
if (dev->speed > 400 ||
dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
internal_clk = 19200;
else if (dev->speed > 100)
internal_clk = 9600;
else
internal_clk = 4000;
fclk = clk_get(dev->dev, "fck");
fclk_rate = clk_get_rate(fclk) / 1000;
clk_put(fclk);
/* Compute prescaler divisor */
psc = fclk_rate / internal_clk;
psc = psc - 1;
/* If configured for High Speed */
if (dev->speed > 400) {
unsigned long scl;
/* For first phase of HS mode */
scl = internal_clk / 400;
fsscll = scl - (scl / 3) - 7;
fssclh = (scl / 3) - 5;
/* For second phase of HS mode */
scl = fclk_rate / dev->speed;
hsscll = scl - (scl / 3) - 7;
hssclh = (scl / 3) - 5;
} else if (dev->speed > 100) {
unsigned long scl;
/* Fast mode */
scl = internal_clk / dev->speed;
fsscll = scl - (scl / 3) - 7;
fssclh = (scl / 3) - 5;
} else {
/* Standard mode */
fsscll = internal_clk / (dev->speed * 2) - 7;
fssclh = internal_clk / (dev->speed * 2) - 5;
}
scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
} else {
/* Program desired operating rate */
fclk_rate /= (psc + 1) * 1000;
if (psc > 2)
psc = 2;
scll = fclk_rate / (dev->speed * 2) - 7 + psc;
sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
}
dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
(OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
dev->pscstate = psc;
dev->scllstate = scll;
dev->sclhstate = sclh;
__omap_i2c_init(dev);
return 0;
}
/*
* Waiting on Bus Busy
*/
static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
{
unsigned long timeout;
timeout = jiffies + OMAP_I2C_TIMEOUT;
while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting for bus ready\n");
return -ETIMEDOUT;
}
msleep(1);
}
return 0;
}
static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
{
u16 buf;
if (dev->flags & OMAP_I2C_FLAG_NO_FIFO)
return;
/*
* Set up notification threshold based on message size. We're doing
* this to try and avoid draining feature as much as possible. Whenever
* we have big messages to transfer (bigger than our total fifo size)
* then we might use draining feature to transfer the remaining bytes.
*/
dev->threshold = clamp(size, (u8) 1, dev->fifo_size);
buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
if (is_rx) {
/* Clear RX Threshold */
buf &= ~(0x3f << 8);
buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
} else {
/* Clear TX Threshold */
buf &= ~0x3f;
buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
}
omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
if (dev->rev < OMAP_I2C_REV_ON_3630)
dev->b_hw = 1; /* Enable hardware fixes */
/* calculate wakeup latency constraint for MPU */
if (dev->set_mpu_wkup_lat != NULL)
dev->latency = (1000000 * dev->threshold) /
(1000 * dev->speed / 8);
}
/*
* Low level master read/write transaction.
*/
static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
struct i2c_msg *msg, int stop)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
unsigned long timeout;
u16 w;
dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
msg->addr, msg->len, msg->flags, stop);
if (msg->len == 0)
return -EINVAL;
dev->receiver = !!(msg->flags & I2C_M_RD);
omap_i2c_resize_fifo(dev, msg->len, dev->receiver);
omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
dev->buf = msg->buf;
dev->buf_len = msg->len;
/* make sure writes to dev->buf_len are ordered */
barrier();
omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
/* Clear the FIFO Buffers */
w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
INIT_COMPLETION(dev->cmd_complete);
dev->cmd_err = 0;
w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
/* High speed configuration */
if (dev->speed > 400)
w |= OMAP_I2C_CON_OPMODE_HS;
if (msg->flags & I2C_M_STOP)
stop = 1;
if (msg->flags & I2C_M_TEN)
w |= OMAP_I2C_CON_XA;
if (!(msg->flags & I2C_M_RD))
w |= OMAP_I2C_CON_TRX;
if (!dev->b_hw && stop)
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
/*
* Don't write stt and stp together on some hardware.
*/
if (dev->b_hw && stop) {
unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
while (con & OMAP_I2C_CON_STT) {
con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
/* Let the user know if i2c is in a bad state */
if (time_after(jiffies, delay)) {
dev_err(dev->dev, "controller timed out "
"waiting for start condition to finish\n");
return -ETIMEDOUT;
}
cpu_relax();
}
w |= OMAP_I2C_CON_STP;
w &= ~OMAP_I2C_CON_STT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
/*
* REVISIT: We should abort the transfer on signals, but the bus goes
* into arbitration and we're currently unable to recover from it.
*/
timeout = wait_for_completion_timeout(&dev->cmd_complete,
OMAP_I2C_TIMEOUT);
if (timeout == 0) {
dev_err(dev->dev, "controller timed out\n");
omap_i2c_reset(dev);
__omap_i2c_init(dev);
return -ETIMEDOUT;
}
if (likely(!dev->cmd_err))
return 0;
/* We have an error */
if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
OMAP_I2C_STAT_XUDF)) {
omap_i2c_reset(dev);
__omap_i2c_init(dev);
return -EIO;
}
if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
if (msg->flags & I2C_M_IGNORE_NAK)
return 0;
if (stop) {
w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
return -EREMOTEIO;
}
return -EIO;
}
/*
* Prepare controller for a transaction and call omap_i2c_xfer_msg
* to do the work during IRQ processing.
*/
static int
omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
int i;
int r;
r = pm_runtime_get_sync(dev->dev);
if (IS_ERR_VALUE(r))
goto out;
r = omap_i2c_wait_for_bb(dev);
if (r < 0)
goto out;
if (dev->set_mpu_wkup_lat != NULL)
dev->set_mpu_wkup_lat(dev->dev, dev->latency);
for (i = 0; i < num; i++) {
r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
if (r != 0)
break;
}
if (r == 0)
r = num;
omap_i2c_wait_for_bb(dev);
if (dev->set_mpu_wkup_lat != NULL)
dev->set_mpu_wkup_lat(dev->dev, -1);
out:
pm_runtime_mark_last_busy(dev->dev);
pm_runtime_put_autosuspend(dev->dev);
return r;
}
static u32
omap_i2c_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
I2C_FUNC_PROTOCOL_MANGLING;
}
static inline void
omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
{
dev->cmd_err |= err;
complete(&dev->cmd_complete);
}
static inline void
omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
{
omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
}
static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
{
/*
* I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
* Not applicable for OMAP4.
* Under certain rare conditions, RDR could be set again
* when the bus is busy, then ignore the interrupt and
* clear the interrupt.
*/
if (stat & OMAP_I2C_STAT_RDR) {
/* Step 1: If RDR is set, clear it */
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
/* Step 2: */
if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
& OMAP_I2C_STAT_BB)) {
/* Step 3: */
if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
& OMAP_I2C_STAT_RDR) {
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
dev_dbg(dev->dev, "RDR when bus is busy.\n");
}
}
}
}
/* rev1 devices are apparently only on some 15xx */
#ifdef CONFIG_ARCH_OMAP15XX
static irqreturn_t
omap_i2c_omap1_isr(int this_irq, void *dev_id)
{
struct omap_i2c_dev *dev = dev_id;
u16 iv, w;
if (pm_runtime_suspended(dev->dev))
return IRQ_NONE;
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
switch (iv) {
case 0x00: /* None */
break;
case 0x01: /* Arbitration lost */
dev_err(dev->dev, "Arbitration lost\n");
omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
break;
case 0x02: /* No acknowledgement */
omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
break;
case 0x03: /* Register access ready */
omap_i2c_complete_cmd(dev, 0);
break;
case 0x04: /* Receive data ready */
if (dev->buf_len) {
w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
*dev->buf++ = w;
dev->buf_len--;
if (dev->buf_len) {
*dev->buf++ = w >> 8;
dev->buf_len--;
}
} else
dev_err(dev->dev, "RRDY IRQ while no data requested\n");
break;
case 0x05: /* Transmit data ready */
if (dev->buf_len) {
w = *dev->buf++;
dev->buf_len--;
if (dev->buf_len) {
w |= *dev->buf++ << 8;
dev->buf_len--;
}
omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
} else
dev_err(dev->dev, "XRDY IRQ while no data to send\n");
break;
default:
return IRQ_NONE;
}
return IRQ_HANDLED;
}
#else
#define omap_i2c_omap1_isr NULL
#endif
/*
* OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
* data to DATA_REG. Otherwise some data bytes can be lost while transferring
* them from the memory to the I2C interface.
*/
static int errata_omap3_i462(struct omap_i2c_dev *dev)
{
unsigned long timeout = 10000;
u16 stat;
do {
stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
if (stat & OMAP_I2C_STAT_XUDF)
break;
if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
OMAP_I2C_STAT_XDR));
if (stat & OMAP_I2C_STAT_NACK) {
dev->cmd_err |= OMAP_I2C_STAT_NACK;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
}
if (stat & OMAP_I2C_STAT_AL) {
dev_err(dev->dev, "Arbitration lost\n");
dev->cmd_err |= OMAP_I2C_STAT_AL;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
}
return -EIO;
}
cpu_relax();
} while (--timeout);
if (!timeout) {
dev_err(dev->dev, "timeout waiting on XUDF bit\n");
return 0;
}
return 0;
}
static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
bool is_rdr)
{
u16 w;
while (num_bytes--) {
w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
*dev->buf++ = w;
dev->buf_len--;
/*
* Data reg in 2430, omap3 and
* omap4 is 8 bit wide
*/
if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
*dev->buf++ = w >> 8;
dev->buf_len--;
}
}
}
static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
bool is_xdr)
{
u16 w;
while (num_bytes--) {
w = *dev->buf++;
dev->buf_len--;
/*
* Data reg in 2430, omap3 and
* omap4 is 8 bit wide
*/
if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
w |= *dev->buf++ << 8;
dev->buf_len--;
}
if (dev->errata & I2C_OMAP_ERRATA_I462) {
int ret;
ret = errata_omap3_i462(dev);
if (ret < 0)
return ret;
}
omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
}
return 0;
}
static irqreturn_t
omap_i2c_isr(int irq, void *dev_id)
{
struct omap_i2c_dev *dev = dev_id;
irqreturn_t ret = IRQ_HANDLED;
u16 mask;
u16 stat;
spin_lock(&dev->lock);
mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
if (stat & mask)
ret = IRQ_WAKE_THREAD;
spin_unlock(&dev->lock);
return ret;
}
static irqreturn_t
omap_i2c_isr_thread(int this_irq, void *dev_id)
{
struct omap_i2c_dev *dev = dev_id;
unsigned long flags;
u16 bits;
u16 stat;
int err = 0, count = 0;
spin_lock_irqsave(&dev->lock, flags);
do {
bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
stat &= bits;
/* If we're in receiver mode, ignore XDR/XRDY */
if (dev->receiver)
stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY);
else
stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY);
if (!stat) {
/* my work here is done */
goto out;
}
dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
if (count++ == 100) {
dev_warn(dev->dev, "Too much work in one IRQ\n");
break;
}
if (stat & OMAP_I2C_STAT_NACK) {
err |= OMAP_I2C_STAT_NACK;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
break;
}
if (stat & OMAP_I2C_STAT_AL) {
dev_err(dev->dev, "Arbitration lost\n");
err |= OMAP_I2C_STAT_AL;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
break;
}
/*
* ProDB0017052: Clear ARDY bit twice
*/
if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
OMAP_I2C_STAT_AL)) {
omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
OMAP_I2C_STAT_RDR |
OMAP_I2C_STAT_XRDY |
OMAP_I2C_STAT_XDR |
OMAP_I2C_STAT_ARDY));
break;
}
if (stat & OMAP_I2C_STAT_RDR) {
u8 num_bytes = 1;
if (dev->fifo_size)
num_bytes = dev->buf_len;
omap_i2c_receive_data(dev, num_bytes, true);
if (dev->errata & I2C_OMAP_ERRATA_I207)
i2c_omap_errata_i207(dev, stat);
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
break;
}
if (stat & OMAP_I2C_STAT_RRDY) {
u8 num_bytes = 1;
if (dev->threshold)
num_bytes = dev->threshold;
omap_i2c_receive_data(dev, num_bytes, false);
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
continue;
}
if (stat & OMAP_I2C_STAT_XDR) {
u8 num_bytes = 1;
int ret;
if (dev->fifo_size)
num_bytes = dev->buf_len;
ret = omap_i2c_transmit_data(dev, num_bytes, true);
if (ret < 0)
break;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
break;
}
if (stat & OMAP_I2C_STAT_XRDY) {
u8 num_bytes = 1;
int ret;
if (dev->threshold)
num_bytes = dev->threshold;
ret = omap_i2c_transmit_data(dev, num_bytes, false);
if (ret < 0)
break;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
continue;
}
if (stat & OMAP_I2C_STAT_ROVR) {
dev_err(dev->dev, "Receive overrun\n");
err |= OMAP_I2C_STAT_ROVR;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
break;
}
if (stat & OMAP_I2C_STAT_XUDF) {
dev_err(dev->dev, "Transmit underflow\n");
err |= OMAP_I2C_STAT_XUDF;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
break;
}
} while (stat);
omap_i2c_complete_cmd(dev, err);
out:
spin_unlock_irqrestore(&dev->lock, flags);
return IRQ_HANDLED;
}
static const struct i2c_algorithm omap_i2c_algo = {
.master_xfer = omap_i2c_xfer,
.functionality = omap_i2c_func,
};
#ifdef CONFIG_OF
static struct omap_i2c_bus_platform_data omap3_pdata = {
.rev = OMAP_I2C_IP_VERSION_1,
.flags = OMAP_I2C_FLAG_BUS_SHIFT_2,
};
static struct omap_i2c_bus_platform_data omap4_pdata = {
.rev = OMAP_I2C_IP_VERSION_2,
};
static const struct of_device_id omap_i2c_of_match[] = {
{
.compatible = "ti,omap4-i2c",
.data = &omap4_pdata,
},
{
.compatible = "ti,omap3-i2c",
.data = &omap3_pdata,
},
{ },
};
MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
#endif
#define OMAP_I2C_SCHEME(rev) ((rev & 0xc000) >> 14)
#define OMAP_I2C_REV_SCHEME_0_MAJOR(rev) (rev >> 4)
#define OMAP_I2C_REV_SCHEME_0_MINOR(rev) (rev & 0xf)
#define OMAP_I2C_REV_SCHEME_1_MAJOR(rev) ((rev & 0x0700) >> 7)
#define OMAP_I2C_REV_SCHEME_1_MINOR(rev) (rev & 0x1f)
#define OMAP_I2C_SCHEME_0 0
#define OMAP_I2C_SCHEME_1 1
static int
omap_i2c_probe(struct platform_device *pdev)
{
struct omap_i2c_dev *dev;
struct i2c_adapter *adap;
struct resource *mem;
const struct omap_i2c_bus_platform_data *pdata =
pdev->dev.platform_data;
struct device_node *node = pdev->dev.of_node;
const struct of_device_id *match;
int irq;
int r;
u32 rev;
u16 minor, major, scheme;
/* NOTE: driver uses the static register mapping */
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
dev_err(&pdev->dev, "no mem resource?\n");
return -ENODEV;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "no irq resource?\n");
return irq;
}
dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
if (!dev) {
dev_err(&pdev->dev, "Menory allocation failed\n");
return -ENOMEM;
}
dev->base = devm_request_and_ioremap(&pdev->dev, mem);
if (!dev->base) {
dev_err(&pdev->dev, "I2C region already claimed\n");
return -ENOMEM;
}
match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
if (match) {
u32 freq = 100000; /* default to 100000 Hz */
pdata = match->data;
dev->flags = pdata->flags;
of_property_read_u32(node, "clock-frequency", &freq);
/* convert DT freq value in Hz into kHz for speed */
dev->speed = freq / 1000;
} else if (pdata != NULL) {
dev->speed = pdata->clkrate;
dev->flags = pdata->flags;
dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
}
dev->pins = devm_pinctrl_get_select_default(&pdev->dev);
if (IS_ERR(dev->pins)) {
if (PTR_ERR(dev->pins) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_warn(&pdev->dev, "did not get pins for i2c error: %li\n",
PTR_ERR(dev->pins));
dev->pins = NULL;
}
dev->dev = &pdev->dev;
dev->irq = irq;
spin_lock_init(&dev->lock);
platform_set_drvdata(pdev, dev);
init_completion(&dev->cmd_complete);
dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
i2c-omap: fix OOPS in omap_i2c_unidle() during probe Commit d84d3ea317ce0db89ce0903b4037f800c5d4c477 added register shift to allow also 16-bit register access. However, omap_i2c_unidle() is called before these are set which causes the following OOPS: Unhandled fault: alignment exception (0x801) at 0xfa070009 Internal error: : 801 [#1] last sysfs file: Modules linked in: CPU: 0 Not tainted (2.6.34-rc2-00052-gae6be51 #3) PC is at omap_i2c_unidle+0x44/0x138 LR is at trace_hardirqs_on_caller+0x158/0x18c pc : [<c01cd2c4>] lr : [<c00743f8>] psr: 20000013 sp : cfc2bf10 ip : 00000009 fp : 00000000 r10: 00000000 r9 : 00000000 r8 : c0378560 r7 : c0378b88 r6 : c0378558 r5 : cfcadc00 r4 : cfcadc00 r3 : 00000009 r2 : fa070000 r1 : 00000000 r0 : 00000000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 10c5387f Table: 80004019 DAC: 00000017 Process swapper (pid: 1, stack limit = 0xcfc2a2e8) Stack: (0xcfc2bf10 to 0xcfc2c000) bf00: c0372cf8 c027225c 00000000 c0a69678 bf20: cfc3e508 c0500898 c0378560 c0378560 c0500898 cfcac8c0 c04fc280 c017d4f4 bf40: c0378560 c017c63c c0378560 c0378594 c0500898 cfcac8c0 c04fc280 c017c754 bf60: 00000000 c017c6f4 c0500898 c017beac cfc16a5c cfc3fd94 c0023448 c0500898 bf80: c0500898 c017b7d4 c032dc7f 00000093 cfc28d40 c0023448 00000000 c0500898 bfa0: 00000000 00000000 00000000 c017ca48 c0023448 00000000 c001d274 00000000 bfc0: 00000000 c002b344 00000031 00000000 00000000 00000192 00000000 c0023448 bfe0: 00000000 00000000 00000000 c0008578 00000000 c002c304 ffdfffff ffffffff [<c01cd2c4>] (omap_i2c_unidle+0x44/0x138) from [<c027225c>] (omap_i2c_probe+0x1a4/0x398) [<c027225c>] (omap_i2c_probe+0x1a4/0x398) from [<c017d4f4>] (platform_drv_probe+0x18/0x1c) [<c017d4f4>] (platform_drv_probe+0x18/0x1c) from [<c017c63c>] (driver_probe_device+0xc0/0x178) [<c017c63c>] (driver_probe_device+0xc0/0x178) from [<c017c754>] (__driver_attach+0x60/0x84) [<c017c754>] (__driver_attach+0x60/0x84) from [<c017beac>] (bus_for_each_dev+0x44/0x74) [<c017beac>] (bus_for_each_dev+0x44/0x74) from [<c017b7d4>] (bus_add_driver+0x9c/0x218) [<c017b7d4>] (bus_add_driver+0x9c/0x218) from [<c017ca48>] (driver_register+0xa8/0x130) [<c017ca48>] (driver_register+0xa8/0x130) from [<c002b344>] (do_one_initcall+0x5c/0x1b8) [<c002b344>] (do_one_initcall+0x5c/0x1b8) from [<c0008578>] (kernel_init+0x90/0x144) [<c0008578>] (kernel_init+0x90/0x144) from [<c002c304>] (kernel_thread_exit+0x0/0x8) Code: e5942004 e3a0c009 e1a0331c e3a01000 (e18210b3) ---[ end trace 1b75b31a2719ed1c ]--- This patch moves register shift setting before any register accesses are done. Signed-off-by: Mika Westerberg <ext-mika.1.westerberg@nokia.com> Cc: Cory Maccarrone <darkstar6262@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-03-23 18:12:56 +08:00
pm_runtime_enable(dev->dev);
pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT);
pm_runtime_use_autosuspend(dev->dev);
r = pm_runtime_get_sync(dev->dev);
if (IS_ERR_VALUE(r))
goto err_free_mem;
/*
* Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2.
* On omap1/3/2 Offset 4 is IE Reg the bit [15:14] is 0 at reset.
* Also since the omap_i2c_read_reg uses reg_map_ip_* a
* raw_readw is done.
*/
rev = __raw_readw(dev->base + 0x04);
scheme = OMAP_I2C_SCHEME(rev);
switch (scheme) {
case OMAP_I2C_SCHEME_0:
dev->regs = (u8 *)reg_map_ip_v1;
dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG);
minor = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
major = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
break;
case OMAP_I2C_SCHEME_1:
/* FALLTHROUGH */
default:
dev->regs = (u8 *)reg_map_ip_v2;
rev = (rev << 16) |
omap_i2c_read_reg(dev, OMAP_I2C_IP_V2_REVNB_LO);
minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev);
major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev);
dev->rev = rev;
}
dev->errata = 0;
if (dev->rev >= OMAP_I2C_REV_ON_2430 &&
dev->rev < OMAP_I2C_REV_ON_4430_PLUS)
dev->errata |= I2C_OMAP_ERRATA_I207;
if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
dev->errata |= I2C_OMAP_ERRATA_I462;
if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
u16 s;
/* Set up the fifo size - Get total size */
s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
dev->fifo_size = 0x8 << s;
/*
* Set up notification threshold as half the total available
* size. This is to ensure that we can handle the status on int
* call back latencies.
*/
dev->fifo_size = (dev->fifo_size / 2);
if (dev->rev < OMAP_I2C_REV_ON_3630)
dev->b_hw = 1; /* Enable hardware fixes */
/* calculate wakeup latency constraint for MPU */
if (dev->set_mpu_wkup_lat != NULL)
dev->latency = (1000000 * dev->fifo_size) /
(1000 * dev->speed / 8);
}
/* reset ASAP, clearing any IRQs */
omap_i2c_init(dev);
if (dev->rev < OMAP_I2C_OMAP1_REV_2)
r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr,
IRQF_NO_SUSPEND, pdev->name, dev);
else
r = devm_request_threaded_irq(&pdev->dev, dev->irq,
omap_i2c_isr, omap_i2c_isr_thread,
IRQF_NO_SUSPEND | IRQF_ONESHOT,
pdev->name, dev);
if (r) {
dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
goto err_unuse_clocks;
}
adap = &dev->adapter;
i2c_set_adapdata(adap, dev);
adap->owner = THIS_MODULE;
adap->class = I2C_CLASS_HWMON;
strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
adap->algo = &omap_i2c_algo;
adap->dev.parent = &pdev->dev;
adap->dev.of_node = pdev->dev.of_node;
/* i2c device drivers may be active on return from add_adapter() */
adap->nr = pdev->id;
r = i2c_add_numbered_adapter(adap);
if (r) {
dev_err(dev->dev, "failure adding adapter\n");
goto err_unuse_clocks;
}
dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr,
major, minor, dev->speed);
of_i2c_register_devices(adap);
pm_runtime_mark_last_busy(dev->dev);
pm_runtime_put_autosuspend(dev->dev);
return 0;
err_unuse_clocks:
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
pm_runtime_put(dev->dev);
pm_runtime_disable(&pdev->dev);
err_free_mem:
platform_set_drvdata(pdev, NULL);
return r;
}
static int omap_i2c_remove(struct platform_device *pdev)
{
struct omap_i2c_dev *dev = platform_get_drvdata(pdev);
int ret;
platform_set_drvdata(pdev, NULL);
i2c_del_adapter(&dev->adapter);
ret = pm_runtime_get_sync(&pdev->dev);
if (IS_ERR_VALUE(ret))
return ret;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
I2C: OMAP: Fix the crash in i2c remove In omap_i2c_remove we are accessing the I2C_CON register without enabling the clocks. Fix the same by ensure device is accessible by calling pm_runtime_get_sync before accessing the registers and calling pm_runtime_put after accessing. This fixes the following crash. [ 154.723022] ------------[ cut here ]------------ [ 154.725677] WARNING: at arch/arm/mach-omap2/omap_l3_noc.c:112 l3_interrupt_handler+0x1b4/0x1c4() [ 154.725677] L3 custom error: MASTER:MPU TARGET:L4 PER2 [ 154.742614] Modules linked in: i2c_omap(-) [ 154.746948] Backtrace: [ 154.746948] [<c0013078>] (dump_backtrace+0x0/0x110) from [<c026c158>] (dump_stack+0x18/0x1c) [ 154.752716] r6:00000070 r5:c002c43c r4:df9b9e98 r3:df9b8000 [ 154.764465] [<c026c140>] (dump_stack+0x0/0x1c) from [<c0041a2c>] (warn_slowpath_common+0x5c/0x6c) [ 154.768341] [<c00419d0>] (warn_slowpath_common+0x0/0x6c) from [<c0041ae0>] (warn_slowpath_fmt+0x38/0x40) [ 154.776153] r8:00000180 r7:c0361594 r6:c0379b48 r5:00080003 r4:e0838b00 [ 154.790771] r3:00000009 [ 154.791778] [<c0041aa8>] (warn_slowpath_fmt+0x0/0x40) from [<c002c43c>] (l3_interrupt_handler+0x1b4/0x1c4) [ 154.803710] r3:c0361598 r2:c02ef74c [ 154.807403] [<c002c288>] (l3_interrupt_handler+0x0/0x1c4) from [<c0085f44>] (handle_irq_event_percpu+0x58/0 [ 154.818237] r8:0000002a r7:00000000 r6:00000000 r5:df808054 r4:df8893c0 [ 154.825378] [<c0085eec>] (handle_irq_event_percpu+0x0/0x188) from [<c00860b8>] (handle_irq_event+0x44/0x64) [ 154.835662] [<c0086074>] (handle_irq_event+0x0/0x64) from [<c0088ec0>] (handle_fasteoi_irq+0xa4/0x10c) [ 154.845458] r6:0000002a r5:df808054 r4:df808000 r3:c034a150 [ 154.846466] [<c0088e1c>] (handle_fasteoi_irq+0x0/0x10c) from [<c0085ed0>] (generic_handle_irq+0x30/0x38) [ 154.854278] r5:c034aa48 r4:0000002a [ 154.862091] [<c0085ea0>] (generic_handle_irq+0x0/0x38) from [<c000fd38>] (handle_IRQ+0x60/0xc0) [ 154.874450] r4:c034ea70 r3:000001f8 [ 154.878234] [<c000fcd8>] (handle_IRQ+0x0/0xc0) from [<c0008478>] (gic_handle_irq+0x20/0x5c) [ 154.887023] r7:ffffff40 r6:df9b9fb0 r5:c034e2b4 r4:0000001a [ 154.887054] [<c0008458>] (gic_handle_irq+0x0/0x5c) from [<c000ea80>] (__irq_usr+0x40/0x60) [ 154.901153] Exception stack(0xdf9b9fb0 to 0xdf9b9ff8) [ 154.907104] 9fa0: beaf1f04 4006be00 0000000f 0000000c [ 154.915710] 9fc0: 4006c000 00000000 00008034 ffffff40 00000007 00000000 00000000 0007b8d7 [ 154.916778] 9fe0: 00000000 beaf1b68 0000d23c 4005baf0 80000010 ffffffff [ 154.931335] r6:ffffffff r5:80000010 r4:4005baf0 r3:beaf1f04 [ 154.937316] ---[ end trace 1b75b31a2719ed21 ]-- Cc: Rajendra Nayak <rnayak@ti.com> Cc: Linux PM list <linux-pm@vger.kernel.org> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-05-29 18:56:18 +08:00
pm_runtime_put(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return 0;
}
#ifdef CONFIG_PM
#ifdef CONFIG_PM_RUNTIME
static int omap_i2c_runtime_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
_dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
} else {
omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
/* Flush posted write */
omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
}
return 0;
}
static int omap_i2c_runtime_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
if (!_dev->regs)
return 0;
__omap_i2c_init(_dev);
return 0;
}
#endif /* CONFIG_PM_RUNTIME */
static struct dev_pm_ops omap_i2c_pm_ops = {
SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
omap_i2c_runtime_resume, NULL)
};
#define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
#else
#define OMAP_I2C_PM_OPS NULL
#endif /* CONFIG_PM */
static struct platform_driver omap_i2c_driver = {
.probe = omap_i2c_probe,
.remove = omap_i2c_remove,
.driver = {
.name = "omap_i2c",
.owner = THIS_MODULE,
.pm = OMAP_I2C_PM_OPS,
.of_match_table = of_match_ptr(omap_i2c_of_match),
},
};
/* I2C may be needed to bring up other drivers */
static int __init
omap_i2c_init_driver(void)
{
return platform_driver_register(&omap_i2c_driver);
}
subsys_initcall(omap_i2c_init_driver);
static void __exit omap_i2c_exit_driver(void)
{
platform_driver_unregister(&omap_i2c_driver);
}
module_exit(omap_i2c_exit_driver);
MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:omap_i2c");