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-rw-r--r--drivers/i2c/busses/i2c-omap.c420
1 files changed, 328 insertions, 92 deletions
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 608038d64f81..be8ee2cac8bb 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -2,13 +2,16 @@
* TI OMAP I2C master mode driver
*
* Copyright (C) 2003 MontaVista Software, Inc.
- * Copyright (C) 2004 Texas Instruments.
- *
- * Updated to work with multiple I2C interfaces on 24xx by
- * Tony Lindgren <tony@atomide.com> and Imre Deak <imre.deak@nokia.com>
* Copyright (C) 2005 Nokia Corporation
+ * Copyright (C) 2004 - 2007 Texas Instruments.
*
- * Cleaned up by Juha Yrjölä <juha.yrjola@nokia.com>
+ * 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
@@ -33,8 +36,14 @@
#include <linux/completion.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
+#include <linux/io.h>
+
+/* I2C controller revisions */
+#define OMAP_I2C_REV_2 0x20
-#include <asm/io.h>
+/* I2C controller revisions present on specific hardware */
+#define OMAP_I2C_REV_ON_2430 0x36
+#define OMAP_I2C_REV_ON_3430 0x3C
/* timeout waiting for the controller to respond */
#define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
@@ -43,6 +52,8 @@
#define OMAP_I2C_IE_REG 0x04
#define OMAP_I2C_STAT_REG 0x08
#define OMAP_I2C_IV_REG 0x0c
+/* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
+#define OMAP_I2C_WE_REG 0x0c
#define OMAP_I2C_SYSS_REG 0x10
#define OMAP_I2C_BUF_REG 0x14
#define OMAP_I2C_CNT_REG 0x18
@@ -55,8 +66,11 @@
#define OMAP_I2C_SCLL_REG 0x34
#define OMAP_I2C_SCLH_REG 0x38
#define OMAP_I2C_SYSTEST_REG 0x3c
+#define OMAP_I2C_BUFSTAT_REG 0x40
/* 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 */
@@ -64,7 +78,8 @@
#define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */
/* I2C Status Register (OMAP_I2C_STAT): */
-#define OMAP_I2C_STAT_SBD (1 << 15) /* Single byte data */
+#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 */
@@ -76,13 +91,34 @@
#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) */
@@ -91,6 +127,10 @@
#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 */
@@ -103,17 +143,19 @@
#define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */
#endif
-/* I2C System Status register (OMAP_I2C_SYSS): */
-#define OMAP_I2C_SYSS_RDONE (1 << 0) /* Reset Done */
+/* 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)
-/* I2C System Configuration Register (OMAP_I2C_SYSC): */
-#define OMAP_I2C_SYSC_SRST (1 << 1) /* Soft Reset */
+#define SYSC_IDLEMODE_SMART 0x2
+#define SYSC_CLOCKACTIVITY_FCLK 0x2
-/* REVISIT: Use platform_data instead of module parameters */
-/* Fast Mode = 400 kHz, Standard = 100 kHz */
-static int clock = 100; /* Default: 100 kHz */
-module_param(clock, int, 0);
-MODULE_PARM_DESC(clock, "Set I2C clock in kHz: 400=fast mode (default == 100)");
struct omap_i2c_dev {
struct device *dev;
@@ -123,11 +165,17 @@ struct omap_i2c_dev {
struct clk *fclk; /* Functional clock */
struct completion cmd_complete;
struct resource *ioarea;
+ u32 speed; /* Speed of bus in Khz */
u16 cmd_err;
u8 *buf;
size_t buf_len;
struct i2c_adapter adapter;
- unsigned rev1:1;
+ u8 fifo_size; /* use as flag and value
+ * fifo_size==0 implies no fifo
+ * if set, should be trsh+1
+ */
+ u8 rev;
+ unsigned b_hw:1; /* bad h/w fixes */
unsigned idle:1;
u16 iestate; /* Saved interrupt register */
};
@@ -143,9 +191,9 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
return __raw_readw(i2c_dev->base + reg);
}
-static int omap_i2c_get_clocks(struct omap_i2c_dev *dev)
+static int __init omap_i2c_get_clocks(struct omap_i2c_dev *dev)
{
- if (cpu_is_omap16xx() || cpu_is_omap24xx()) {
+ if (cpu_is_omap16xx() || cpu_class_is_omap2()) {
dev->iclk = clk_get(dev->dev, "i2c_ick");
if (IS_ERR(dev->iclk)) {
dev->iclk = NULL;
@@ -178,25 +226,33 @@ static void omap_i2c_put_clocks(struct omap_i2c_dev *dev)
static void omap_i2c_unidle(struct omap_i2c_dev *dev)
{
+ WARN_ON(!dev->idle);
+
if (dev->iclk != NULL)
clk_enable(dev->iclk);
clk_enable(dev->fclk);
+ dev->idle = 0;
if (dev->iestate)
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
- dev->idle = 0;
}
static void omap_i2c_idle(struct omap_i2c_dev *dev)
{
u16 iv;
- dev->idle = 1;
+ WARN_ON(dev->idle);
+
dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
- if (dev->rev1)
- iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
- else
+ if (dev->rev < OMAP_I2C_REV_2) {
+ iv = 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 before the dev->idle store occurs */
+ omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+ }
+ dev->idle = 1;
clk_disable(dev->fclk);
if (dev->iclk != NULL)
clk_disable(dev->iclk);
@@ -204,18 +260,20 @@ static void omap_i2c_idle(struct omap_i2c_dev *dev)
static int omap_i2c_init(struct omap_i2c_dev *dev)
{
- u16 psc = 0;
+ u16 psc = 0, scll = 0, sclh = 0;
+ u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
unsigned long fclk_rate = 12000000;
unsigned long timeout;
+ unsigned long internal_clk = 0;
- if (!dev->rev1) {
- omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, OMAP_I2C_SYSC_SRST);
+ if (dev->rev >= OMAP_I2C_REV_2) {
+ 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) &
- OMAP_I2C_SYSS_RDONE)) {
+ SYSS_RESETDONE_MASK)) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting "
"for controller reset\n");
@@ -223,6 +281,33 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
}
msleep(1);
}
+
+ /* SYSC register is cleared by the reset; rewrite it */
+ if (dev->rev == OMAP_I2C_REV_ON_2430) {
+
+ omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
+ SYSC_AUTOIDLE_MASK);
+
+ } else if (dev->rev >= OMAP_I2C_REV_ON_3430) {
+ u32 v;
+
+ v = SYSC_AUTOIDLE_MASK;
+ v |= SYSC_ENAWAKEUP_MASK;
+ v |= (SYSC_IDLEMODE_SMART <<
+ __ffs(SYSC_SIDLEMODE_MASK));
+ v |= (SYSC_CLOCKACTIVITY_FCLK <<
+ __ffs(SYSC_CLOCKACTIVITY_MASK));
+
+ omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, v);
+ /*
+ * Enabling all wakup sources to stop I2C freezing on
+ * WFI instruction.
+ * REVISIT: Some wkup sources might not be needed.
+ */
+ omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
+ OMAP_I2C_WE_ALL);
+
+ }
}
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
@@ -249,27 +334,65 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
psc = fclk_rate / 12000000;
}
+ if (cpu_is_omap2430() || cpu_is_omap34xx()) {
+
+ /* HSI2C controller internal clk rate should be 19.2 Mhz */
+ internal_clk = 19200;
+ fclk_rate = clk_get_rate(dev->fclk) / 1000;
+
+ /* Compute prescaler divisor */
+ psc = fclk_rate / internal_clk;
+ psc = psc - 1;
+
+ /* If configured for High Speed */
+ if (dev->speed > 400) {
+ /* For first phase of HS mode */
+ fsscll = internal_clk / (400 * 2) - 6;
+ fssclh = internal_clk / (400 * 2) - 6;
+
+ /* For second phase of HS mode */
+ hsscll = fclk_rate / (dev->speed * 2) - 6;
+ hssclh = fclk_rate / (dev->speed * 2) - 6;
+ } else {
+ /* To handle F/S modes */
+ fsscll = internal_clk / (dev->speed * 2) - 6;
+ fssclh = internal_clk / (dev->speed * 2) - 6;
+ }
+ 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;
+ }
+
/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
- /* Program desired operating rate */
- fclk_rate /= (psc + 1) * 1000;
- if (psc > 2)
- psc = 2;
+ /* SCL low and high time values */
+ omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
+ omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
- omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG,
- fclk_rate / (clock * 2) - 7 + psc);
- omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG,
- fclk_rate / (clock * 2) - 7 + psc);
+ if (dev->fifo_size)
+ /* Note: setup required fifo size - 1 */
+ omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG,
+ (dev->fifo_size - 1) << 8 | /* RTRSH */
+ OMAP_I2C_BUF_RXFIF_CLR |
+ (dev->fifo_size - 1) | /* XTRSH */
+ OMAP_I2C_BUF_TXFIF_CLR);
/* Take the I2C module out of reset: */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
/* Enable interrupts */
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG,
- (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
- OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
- OMAP_I2C_IE_AL));
+ (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));
return 0;
}
@@ -316,20 +439,59 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
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_TEN)
w |= OMAP_I2C_CON_XA;
if (!(msg->flags & I2C_M_RD))
w |= OMAP_I2C_CON_TRX;
- if (stop)
+
+ if (!dev->b_hw && stop)
w |= OMAP_I2C_CON_STP;
+
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
- r = wait_for_completion_interruptible_timeout(&dev->cmd_complete,
- OMAP_I2C_TIMEOUT);
+ /*
+ * 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.
+ */
+ r = wait_for_completion_timeout(&dev->cmd_complete,
+ OMAP_I2C_TIMEOUT);
dev->buf_len = 0;
if (r < 0)
return r;
@@ -376,7 +538,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
omap_i2c_unidle(dev);
- if ((r = omap_i2c_wait_for_bb(dev)) < 0)
+ r = omap_i2c_wait_for_bb(dev);
+ if (r < 0)
goto out;
for (i = 0; i < num; i++) {
@@ -411,6 +574,9 @@ omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
}
+/* rev1 devices are apparently only on some 15xx */
+#ifdef CONFIG_ARCH_OMAP15XX
+
static irqreturn_t
omap_i2c_rev1_isr(int this_irq, void *dev_id)
{
@@ -465,6 +631,9 @@ omap_i2c_rev1_isr(int this_irq, void *dev_id)
return IRQ_HANDLED;
}
+#else
+#define omap_i2c_rev1_isr NULL
+#endif
static irqreturn_t
omap_i2c_isr(int this_irq, void *dev_id)
@@ -472,7 +641,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
struct omap_i2c_dev *dev = dev_id;
u16 bits;
u16 stat, w;
- int count = 0;
+ int err, count = 0;
if (dev->idle)
return IRQ_NONE;
@@ -487,39 +656,96 @@ omap_i2c_isr(int this_irq, void *dev_id)
omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
- if (stat & OMAP_I2C_STAT_ARDY) {
- omap_i2c_complete_cmd(dev, 0);
- continue;
+ err = 0;
+ if (stat & OMAP_I2C_STAT_NACK) {
+ err |= OMAP_I2C_STAT_NACK;
+ omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
+ OMAP_I2C_CON_STP);
}
- if (stat & OMAP_I2C_STAT_RRDY) {
- w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
- if (dev->buf_len) {
- *dev->buf++ = w;
- dev->buf_len--;
+ if (stat & OMAP_I2C_STAT_AL) {
+ dev_err(dev->dev, "Arbitration lost\n");
+ err |= OMAP_I2C_STAT_AL;
+ }
+ if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
+ OMAP_I2C_STAT_AL))
+ omap_i2c_complete_cmd(dev, err);
+ if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
+ u8 num_bytes = 1;
+ if (dev->fifo_size) {
+ if (stat & OMAP_I2C_STAT_RRDY)
+ num_bytes = dev->fifo_size;
+ else
+ num_bytes = omap_i2c_read_reg(dev,
+ OMAP_I2C_BUFSTAT_REG);
+ }
+ while (num_bytes) {
+ num_bytes--;
+ w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
if (dev->buf_len) {
- *dev->buf++ = w >> 8;
+ *dev->buf++ = w;
dev->buf_len--;
+ /* Data reg from 2430 is 8 bit wide */
+ if (!cpu_is_omap2430() &&
+ !cpu_is_omap34xx()) {
+ if (dev->buf_len) {
+ *dev->buf++ = w >> 8;
+ dev->buf_len--;
+ }
+ }
+ } else {
+ if (stat & OMAP_I2C_STAT_RRDY)
+ dev_err(dev->dev,
+ "RRDY IRQ while no data"
+ " requested\n");
+ if (stat & OMAP_I2C_STAT_RDR)
+ dev_err(dev->dev,
+ "RDR IRQ while no data"
+ " requested\n");
+ break;
}
- } else
- dev_err(dev->dev, "RRDY IRQ while no data "
- "requested\n");
- omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
+ }
+ omap_i2c_ack_stat(dev,
+ stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
continue;
}
- if (stat & OMAP_I2C_STAT_XRDY) {
- w = 0;
- if (dev->buf_len) {
- w = *dev->buf++;
- dev->buf_len--;
+ if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
+ u8 num_bytes = 1;
+ if (dev->fifo_size) {
+ if (stat & OMAP_I2C_STAT_XRDY)
+ num_bytes = dev->fifo_size;
+ else
+ num_bytes = omap_i2c_read_reg(dev,
+ OMAP_I2C_BUFSTAT_REG);
+ }
+ while (num_bytes) {
+ num_bytes--;
+ w = 0;
if (dev->buf_len) {
- w |= *dev->buf++ << 8;
+ w = *dev->buf++;
dev->buf_len--;
+ /* Data reg from 2430 is 8 bit wide */
+ if (!cpu_is_omap2430() &&
+ !cpu_is_omap34xx()) {
+ if (dev->buf_len) {
+ w |= *dev->buf++ << 8;
+ dev->buf_len--;
+ }
+ }
+ } else {
+ if (stat & OMAP_I2C_STAT_XRDY)
+ dev_err(dev->dev,
+ "XRDY IRQ while no "
+ "data to send\n");
+ if (stat & OMAP_I2C_STAT_XDR)
+ dev_err(dev->dev,
+ "XDR IRQ while no "
+ "data to send\n");
+ break;
}
- } else
- dev_err(dev->dev, "XRDY IRQ while no "
- "data to send\n");
- omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
- omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
+ omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
+ }
+ omap_i2c_ack_stat(dev,
+ stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
continue;
}
if (stat & OMAP_I2C_STAT_ROVR) {
@@ -527,18 +753,9 @@ omap_i2c_isr(int this_irq, void *dev_id)
dev->cmd_err |= OMAP_I2C_STAT_ROVR;
}
if (stat & OMAP_I2C_STAT_XUDF) {
- dev_err(dev->dev, "Transmit overflow\n");
+ dev_err(dev->dev, "Transmit underflow\n");
dev->cmd_err |= OMAP_I2C_STAT_XUDF;
}
- if (stat & OMAP_I2C_STAT_NACK) {
- omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
- omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
- OMAP_I2C_CON_STP);
- }
- if (stat & OMAP_I2C_STAT_AL) {
- dev_err(dev->dev, "Arbitration lost\n");
- omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
- }
}
return count ? IRQ_HANDLED : IRQ_NONE;
@@ -549,13 +766,15 @@ static const struct i2c_algorithm omap_i2c_algo = {
.functionality = omap_i2c_func,
};
-static int
+static int __init
omap_i2c_probe(struct platform_device *pdev)
{
struct omap_i2c_dev *dev;
struct i2c_adapter *adap;
struct resource *mem, *irq, *ioarea;
+ irq_handler_t isr;
int r;
+ u32 speed = 0;
/* NOTE: driver uses the static register mapping */
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -576,17 +795,19 @@ omap_i2c_probe(struct platform_device *pdev)
return -EBUSY;
}
- if (clock > 200)
- clock = 400; /* Fast mode */
- else
- clock = 100; /* Standard mode */
-
dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
if (!dev) {
r = -ENOMEM;
goto err_release_region;
}
+ if (pdev->dev.platform_data != NULL)
+ speed = *(u32 *)pdev->dev.platform_data;
+ else
+ speed = 100; /* Defualt speed */
+
+ dev->speed = speed;
+ dev->idle = 1;
dev->dev = &pdev->dev;
dev->irq = irq->start;
dev->base = ioremap(mem->start, mem->end - mem->start + 1);
@@ -602,22 +823,39 @@ omap_i2c_probe(struct platform_device *pdev)
omap_i2c_unidle(dev);
- if (cpu_is_omap15xx())
- dev->rev1 = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) < 0x20;
+ dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
+
+ if (cpu_is_omap2430() || cpu_is_omap34xx()) {
+ 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);
+ dev->b_hw = 1; /* Enable hardware fixes */
+ }
/* reset ASAP, clearing any IRQs */
omap_i2c_init(dev);
- r = request_irq(dev->irq, dev->rev1 ? omap_i2c_rev1_isr : omap_i2c_isr,
- 0, pdev->name, dev);
+ isr = (dev->rev < OMAP_I2C_REV_2) ? omap_i2c_rev1_isr : omap_i2c_isr;
+ r = request_irq(dev->irq, isr, 0, pdev->name, dev);
if (r) {
dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
goto err_unuse_clocks;
}
- r = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
+
dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n",
- pdev->id, r >> 4, r & 0xf, clock);
+ pdev->id, dev->rev >> 4, dev->rev & 0xf, dev->speed);
+
+ omap_i2c_idle(dev);
adap = &dev->adapter;
i2c_set_adapdata(adap, dev);
@@ -635,8 +873,6 @@ omap_i2c_probe(struct platform_device *pdev)
goto err_free_irq;
}
- omap_i2c_idle(dev);
-
return 0;
err_free_irq:
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.