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path: root/drivers/i2c/busses/i2c-pnx.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-pnx.c')
-rw-r--r--drivers/i2c/busses/i2c-pnx.c792
1 files changed, 792 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c
new file mode 100644
index 000000000..50f21cdbe
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pnx.c
@@ -0,0 +1,792 @@
+/*
+ * Provides I2C support for Philips PNX010x/PNX4008 boards.
+ *
+ * Authors: Dennis Kovalev <dkovalev@ru.mvista.com>
+ * Vitaly Wool <vwool@ru.mvista.com>
+ *
+ * 2004-2006 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/timer.h>
+#include <linux/completion.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+
+#define I2C_PNX_TIMEOUT_DEFAULT 10 /* msec */
+#define I2C_PNX_SPEED_KHZ_DEFAULT 100
+#define I2C_PNX_REGION_SIZE 0x100
+
+struct i2c_pnx_mif {
+ int ret; /* Return value */
+ int mode; /* Interface mode */
+ struct completion complete; /* I/O completion */
+ struct timer_list timer; /* Timeout */
+ u8 * buf; /* Data buffer */
+ int len; /* Length of data buffer */
+ int order; /* RX Bytes to order via TX */
+};
+
+struct i2c_pnx_algo_data {
+ void __iomem *ioaddr;
+ struct i2c_pnx_mif mif;
+ int last;
+ struct clk *clk;
+ struct i2c_adapter adapter;
+ int irq;
+ u32 timeout;
+};
+
+enum {
+ mstatus_tdi = 0x00000001,
+ mstatus_afi = 0x00000002,
+ mstatus_nai = 0x00000004,
+ mstatus_drmi = 0x00000008,
+ mstatus_active = 0x00000020,
+ mstatus_scl = 0x00000040,
+ mstatus_sda = 0x00000080,
+ mstatus_rff = 0x00000100,
+ mstatus_rfe = 0x00000200,
+ mstatus_tff = 0x00000400,
+ mstatus_tfe = 0x00000800,
+};
+
+enum {
+ mcntrl_tdie = 0x00000001,
+ mcntrl_afie = 0x00000002,
+ mcntrl_naie = 0x00000004,
+ mcntrl_drmie = 0x00000008,
+ mcntrl_drsie = 0x00000010,
+ mcntrl_rffie = 0x00000020,
+ mcntrl_daie = 0x00000040,
+ mcntrl_tffie = 0x00000080,
+ mcntrl_reset = 0x00000100,
+ mcntrl_cdbmode = 0x00000400,
+};
+
+enum {
+ rw_bit = 1 << 0,
+ start_bit = 1 << 8,
+ stop_bit = 1 << 9,
+};
+
+#define I2C_REG_RX(a) ((a)->ioaddr) /* Rx FIFO reg (RO) */
+#define I2C_REG_TX(a) ((a)->ioaddr) /* Tx FIFO reg (WO) */
+#define I2C_REG_STS(a) ((a)->ioaddr + 0x04) /* Status reg (RO) */
+#define I2C_REG_CTL(a) ((a)->ioaddr + 0x08) /* Ctl reg */
+#define I2C_REG_CKL(a) ((a)->ioaddr + 0x0c) /* Clock divider low */
+#define I2C_REG_CKH(a) ((a)->ioaddr + 0x10) /* Clock divider high */
+#define I2C_REG_ADR(a) ((a)->ioaddr + 0x14) /* I2C address */
+#define I2C_REG_RFL(a) ((a)->ioaddr + 0x18) /* Rx FIFO level (RO) */
+#define I2C_REG_TFL(a) ((a)->ioaddr + 0x1c) /* Tx FIFO level (RO) */
+#define I2C_REG_RXB(a) ((a)->ioaddr + 0x20) /* Num of bytes Rx-ed (RO) */
+#define I2C_REG_TXB(a) ((a)->ioaddr + 0x24) /* Num of bytes Tx-ed (RO) */
+#define I2C_REG_TXS(a) ((a)->ioaddr + 0x28) /* Tx slave FIFO (RO) */
+#define I2C_REG_STFL(a) ((a)->ioaddr + 0x2c) /* Tx slave FIFO level (RO) */
+
+static inline int wait_timeout(struct i2c_pnx_algo_data *data)
+{
+ long timeout = data->timeout;
+ while (timeout > 0 &&
+ (ioread32(I2C_REG_STS(data)) & mstatus_active)) {
+ mdelay(1);
+ timeout--;
+ }
+ return (timeout <= 0);
+}
+
+static inline int wait_reset(struct i2c_pnx_algo_data *data)
+{
+ long timeout = data->timeout;
+ while (timeout > 0 &&
+ (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) {
+ mdelay(1);
+ timeout--;
+ }
+ return (timeout <= 0);
+}
+
+static inline void i2c_pnx_arm_timer(struct i2c_pnx_algo_data *alg_data)
+{
+ struct timer_list *timer = &alg_data->mif.timer;
+ unsigned long expires = msecs_to_jiffies(alg_data->timeout);
+
+ if (expires <= 1)
+ expires = 2;
+
+ del_timer_sync(timer);
+
+ dev_dbg(&alg_data->adapter.dev, "Timer armed at %lu plus %lu jiffies.\n",
+ jiffies, expires);
+
+ timer->expires = jiffies + expires;
+
+ add_timer(timer);
+}
+
+/**
+ * i2c_pnx_start - start a device
+ * @slave_addr: slave address
+ * @alg_data: pointer to local driver data structure
+ *
+ * Generate a START signal in the desired mode.
+ */
+static int i2c_pnx_start(unsigned char slave_addr,
+ struct i2c_pnx_algo_data *alg_data)
+{
+ dev_dbg(&alg_data->adapter.dev, "%s(): addr 0x%x mode %d\n", __func__,
+ slave_addr, alg_data->mif.mode);
+
+ /* Check for 7 bit slave addresses only */
+ if (slave_addr & ~0x7f) {
+ dev_err(&alg_data->adapter.dev,
+ "%s: Invalid slave address %x. Only 7-bit addresses are supported\n",
+ alg_data->adapter.name, slave_addr);
+ return -EINVAL;
+ }
+
+ /* First, make sure bus is idle */
+ if (wait_timeout(alg_data)) {
+ /* Somebody else is monopolizing the bus */
+ dev_err(&alg_data->adapter.dev,
+ "%s: Bus busy. Slave addr = %02x, cntrl = %x, stat = %x\n",
+ alg_data->adapter.name, slave_addr,
+ ioread32(I2C_REG_CTL(alg_data)),
+ ioread32(I2C_REG_STS(alg_data)));
+ return -EBUSY;
+ } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) {
+ /* Sorry, we lost the bus */
+ dev_err(&alg_data->adapter.dev,
+ "%s: Arbitration failure. Slave addr = %02x\n",
+ alg_data->adapter.name, slave_addr);
+ return -EIO;
+ }
+
+ /*
+ * OK, I2C is enabled and we have the bus.
+ * Clear the current TDI and AFI status flags.
+ */
+ iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi,
+ I2C_REG_STS(alg_data));
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): sending %#x\n", __func__,
+ (slave_addr << 1) | start_bit | alg_data->mif.mode);
+
+ /* Write the slave address, START bit and R/W bit */
+ iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode,
+ I2C_REG_TX(alg_data));
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): exit\n", __func__);
+
+ return 0;
+}
+
+/**
+ * i2c_pnx_stop - stop a device
+ * @alg_data: pointer to local driver data structure
+ *
+ * Generate a STOP signal to terminate the master transaction.
+ */
+static void i2c_pnx_stop(struct i2c_pnx_algo_data *alg_data)
+{
+ /* Only 1 msec max timeout due to interrupt context */
+ long timeout = 1000;
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n",
+ __func__, ioread32(I2C_REG_STS(alg_data)));
+
+ /* Write a STOP bit to TX FIFO */
+ iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data));
+
+ /* Wait until the STOP is seen. */
+ while (timeout > 0 &&
+ (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) {
+ /* may be called from interrupt context */
+ udelay(1);
+ timeout--;
+ }
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n",
+ __func__, ioread32(I2C_REG_STS(alg_data)));
+}
+
+/**
+ * i2c_pnx_master_xmit - transmit data to slave
+ * @alg_data: pointer to local driver data structure
+ *
+ * Sends one byte of data to the slave
+ */
+static int i2c_pnx_master_xmit(struct i2c_pnx_algo_data *alg_data)
+{
+ u32 val;
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n",
+ __func__, ioread32(I2C_REG_STS(alg_data)));
+
+ if (alg_data->mif.len > 0) {
+ /* We still have something to talk about... */
+ val = *alg_data->mif.buf++;
+
+ if (alg_data->mif.len == 1)
+ val |= stop_bit;
+
+ alg_data->mif.len--;
+ iowrite32(val, I2C_REG_TX(alg_data));
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): xmit %#x [%d]\n",
+ __func__, val, alg_data->mif.len + 1);
+
+ if (alg_data->mif.len == 0) {
+ if (alg_data->last) {
+ /* Wait until the STOP is seen. */
+ if (wait_timeout(alg_data))
+ dev_err(&alg_data->adapter.dev,
+ "The bus is still active after timeout\n");
+ }
+ /* Disable master interrupts */
+ iowrite32(ioread32(I2C_REG_CTL(alg_data)) &
+ ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie),
+ I2C_REG_CTL(alg_data));
+
+ del_timer_sync(&alg_data->mif.timer);
+
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): Waking up xfer routine.\n",
+ __func__);
+
+ complete(&alg_data->mif.complete);
+ }
+ } else if (alg_data->mif.len == 0) {
+ /* zero-sized transfer */
+ i2c_pnx_stop(alg_data);
+
+ /* Disable master interrupts. */
+ iowrite32(ioread32(I2C_REG_CTL(alg_data)) &
+ ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie),
+ I2C_REG_CTL(alg_data));
+
+ /* Stop timer. */
+ del_timer_sync(&alg_data->mif.timer);
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): Waking up xfer routine after zero-xfer.\n",
+ __func__);
+
+ complete(&alg_data->mif.complete);
+ }
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n",
+ __func__, ioread32(I2C_REG_STS(alg_data)));
+
+ return 0;
+}
+
+/**
+ * i2c_pnx_master_rcv - receive data from slave
+ * @alg_data: pointer to local driver data structure
+ *
+ * Reads one byte data from the slave
+ */
+static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data)
+{
+ unsigned int val = 0;
+ u32 ctl = 0;
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n",
+ __func__, ioread32(I2C_REG_STS(alg_data)));
+
+ /* Check, whether there is already data,
+ * or we didn't 'ask' for it yet.
+ */
+ if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) {
+ /* 'Asking' is done asynchronously, e.g. dummy TX of several
+ * bytes is done before the first actual RX arrives in FIFO.
+ * Therefore, ordered bytes (via TX) are counted separately.
+ */
+ if (alg_data->mif.order) {
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): Write dummy data to fill Rx-fifo...\n",
+ __func__);
+
+ if (alg_data->mif.order == 1) {
+ /* Last byte, do not acknowledge next rcv. */
+ val |= stop_bit;
+
+ /*
+ * Enable interrupt RFDAIE (data in Rx fifo),
+ * and disable DRMIE (need data for Tx)
+ */
+ ctl = ioread32(I2C_REG_CTL(alg_data));
+ ctl |= mcntrl_rffie | mcntrl_daie;
+ ctl &= ~mcntrl_drmie;
+ iowrite32(ctl, I2C_REG_CTL(alg_data));
+ }
+
+ /*
+ * Now we'll 'ask' for data:
+ * For each byte we want to receive, we must
+ * write a (dummy) byte to the Tx-FIFO.
+ */
+ iowrite32(val, I2C_REG_TX(alg_data));
+ alg_data->mif.order--;
+ }
+ return 0;
+ }
+
+ /* Handle data. */
+ if (alg_data->mif.len > 0) {
+ val = ioread32(I2C_REG_RX(alg_data));
+ *alg_data->mif.buf++ = (u8) (val & 0xff);
+ dev_dbg(&alg_data->adapter.dev, "%s(): rcv 0x%x [%d]\n",
+ __func__, val, alg_data->mif.len);
+
+ alg_data->mif.len--;
+ if (alg_data->mif.len == 0) {
+ if (alg_data->last)
+ /* Wait until the STOP is seen. */
+ if (wait_timeout(alg_data))
+ dev_err(&alg_data->adapter.dev,
+ "The bus is still active after timeout\n");
+
+ /* Disable master interrupts */
+ ctl = ioread32(I2C_REG_CTL(alg_data));
+ ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
+ mcntrl_drmie | mcntrl_daie);
+ iowrite32(ctl, I2C_REG_CTL(alg_data));
+
+ /* Kill timer. */
+ del_timer_sync(&alg_data->mif.timer);
+ complete(&alg_data->mif.complete);
+ }
+ }
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n",
+ __func__, ioread32(I2C_REG_STS(alg_data)));
+
+ return 0;
+}
+
+static irqreturn_t i2c_pnx_interrupt(int irq, void *dev_id)
+{
+ struct i2c_pnx_algo_data *alg_data = dev_id;
+ u32 stat, ctl;
+
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): mstat = %x mctrl = %x, mode = %d\n",
+ __func__,
+ ioread32(I2C_REG_STS(alg_data)),
+ ioread32(I2C_REG_CTL(alg_data)),
+ alg_data->mif.mode);
+ stat = ioread32(I2C_REG_STS(alg_data));
+
+ /* let's see what kind of event this is */
+ if (stat & mstatus_afi) {
+ /* We lost arbitration in the midst of a transfer */
+ alg_data->mif.ret = -EIO;
+
+ /* Disable master interrupts. */
+ ctl = ioread32(I2C_REG_CTL(alg_data));
+ ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
+ mcntrl_drmie);
+ iowrite32(ctl, I2C_REG_CTL(alg_data));
+
+ /* Stop timer, to prevent timeout. */
+ del_timer_sync(&alg_data->mif.timer);
+ complete(&alg_data->mif.complete);
+ } else if (stat & mstatus_nai) {
+ /* Slave did not acknowledge, generate a STOP */
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): Slave did not acknowledge, generating a STOP.\n",
+ __func__);
+ i2c_pnx_stop(alg_data);
+
+ /* Disable master interrupts. */
+ ctl = ioread32(I2C_REG_CTL(alg_data));
+ ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
+ mcntrl_drmie);
+ iowrite32(ctl, I2C_REG_CTL(alg_data));
+
+ /* Our return value. */
+ alg_data->mif.ret = -EIO;
+
+ /* Stop timer, to prevent timeout. */
+ del_timer_sync(&alg_data->mif.timer);
+ complete(&alg_data->mif.complete);
+ } else {
+ /*
+ * Two options:
+ * - Master Tx needs data.
+ * - There is data in the Rx-fifo
+ * The latter is only the case if we have requested for data,
+ * via a dummy write. (See 'i2c_pnx_master_rcv'.)
+ * We therefore check, as a sanity check, whether that interrupt
+ * has been enabled.
+ */
+ if ((stat & mstatus_drmi) || !(stat & mstatus_rfe)) {
+ if (alg_data->mif.mode == I2C_SMBUS_WRITE) {
+ i2c_pnx_master_xmit(alg_data);
+ } else if (alg_data->mif.mode == I2C_SMBUS_READ) {
+ i2c_pnx_master_rcv(alg_data);
+ }
+ }
+ }
+
+ /* Clear TDI and AFI bits */
+ stat = ioread32(I2C_REG_STS(alg_data));
+ iowrite32(stat | mstatus_tdi | mstatus_afi, I2C_REG_STS(alg_data));
+
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): exiting, stat = %x ctrl = %x.\n",
+ __func__, ioread32(I2C_REG_STS(alg_data)),
+ ioread32(I2C_REG_CTL(alg_data)));
+
+ return IRQ_HANDLED;
+}
+
+static void i2c_pnx_timeout(struct timer_list *t)
+{
+ struct i2c_pnx_algo_data *alg_data = from_timer(alg_data, t, mif.timer);
+ u32 ctl;
+
+ dev_err(&alg_data->adapter.dev,
+ "Master timed out. stat = %04x, cntrl = %04x. Resetting master...\n",
+ ioread32(I2C_REG_STS(alg_data)),
+ ioread32(I2C_REG_CTL(alg_data)));
+
+ /* Reset master and disable interrupts */
+ ctl = ioread32(I2C_REG_CTL(alg_data));
+ ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | mcntrl_drmie);
+ iowrite32(ctl, I2C_REG_CTL(alg_data));
+
+ ctl |= mcntrl_reset;
+ iowrite32(ctl, I2C_REG_CTL(alg_data));
+ wait_reset(alg_data);
+ alg_data->mif.ret = -EIO;
+ complete(&alg_data->mif.complete);
+}
+
+static inline void bus_reset_if_active(struct i2c_pnx_algo_data *alg_data)
+{
+ u32 stat;
+
+ if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) {
+ dev_err(&alg_data->adapter.dev,
+ "%s: Bus is still active after xfer. Reset it...\n",
+ alg_data->adapter.name);
+ iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
+ I2C_REG_CTL(alg_data));
+ wait_reset(alg_data);
+ } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) {
+ /* If there is data in the fifo's after transfer,
+ * flush fifo's by reset.
+ */
+ iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
+ I2C_REG_CTL(alg_data));
+ wait_reset(alg_data);
+ } else if (stat & mstatus_nai) {
+ iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
+ I2C_REG_CTL(alg_data));
+ wait_reset(alg_data);
+ }
+}
+
+/**
+ * i2c_pnx_xfer - generic transfer entry point
+ * @adap: pointer to I2C adapter structure
+ * @msgs: array of messages
+ * @num: number of messages
+ *
+ * Initiates the transfer
+ */
+static int
+i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+ struct i2c_msg *pmsg;
+ int rc = 0, completed = 0, i;
+ struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+ u32 stat;
+
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): entering: %d messages, stat = %04x.\n",
+ __func__, num, ioread32(I2C_REG_STS(alg_data)));
+
+ bus_reset_if_active(alg_data);
+
+ /* Process transactions in a loop. */
+ for (i = 0; rc >= 0 && i < num; i++) {
+ u8 addr;
+
+ pmsg = &msgs[i];
+ addr = pmsg->addr;
+
+ if (pmsg->flags & I2C_M_TEN) {
+ dev_err(&alg_data->adapter.dev,
+ "%s: 10 bits addr not supported!\n",
+ alg_data->adapter.name);
+ rc = -EINVAL;
+ break;
+ }
+
+ alg_data->mif.buf = pmsg->buf;
+ alg_data->mif.len = pmsg->len;
+ alg_data->mif.order = pmsg->len;
+ alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ?
+ I2C_SMBUS_READ : I2C_SMBUS_WRITE;
+ alg_data->mif.ret = 0;
+ alg_data->last = (i == num - 1);
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): mode %d, %d bytes\n",
+ __func__, alg_data->mif.mode, alg_data->mif.len);
+
+ i2c_pnx_arm_timer(alg_data);
+
+ /* initialize the completion var */
+ init_completion(&alg_data->mif.complete);
+
+ /* Enable master interrupt */
+ iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie |
+ mcntrl_naie | mcntrl_drmie,
+ I2C_REG_CTL(alg_data));
+
+ /* Put start-code and slave-address on the bus. */
+ rc = i2c_pnx_start(addr, alg_data);
+ if (rc < 0)
+ break;
+
+ /* Wait for completion */
+ wait_for_completion(&alg_data->mif.complete);
+
+ if (!(rc = alg_data->mif.ret))
+ completed++;
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): Complete, return code = %d.\n",
+ __func__, rc);
+
+ /* Clear TDI and AFI bits in case they are set. */
+ if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_tdi) {
+ dev_dbg(&alg_data->adapter.dev,
+ "%s: TDI still set... clearing now.\n",
+ alg_data->adapter.name);
+ iowrite32(stat, I2C_REG_STS(alg_data));
+ }
+ if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) {
+ dev_dbg(&alg_data->adapter.dev,
+ "%s: AFI still set... clearing now.\n",
+ alg_data->adapter.name);
+ iowrite32(stat, I2C_REG_STS(alg_data));
+ }
+ }
+
+ bus_reset_if_active(alg_data);
+
+ /* Cleanup to be sure... */
+ alg_data->mif.buf = NULL;
+ alg_data->mif.len = 0;
+ alg_data->mif.order = 0;
+
+ dev_dbg(&alg_data->adapter.dev, "%s(): exiting, stat = %x\n",
+ __func__, ioread32(I2C_REG_STS(alg_data)));
+
+ if (completed != num)
+ return ((rc < 0) ? rc : -EREMOTEIO);
+
+ return num;
+}
+
+static u32 i2c_pnx_func(struct i2c_adapter *adapter)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm pnx_algorithm = {
+ .master_xfer = i2c_pnx_xfer,
+ .functionality = i2c_pnx_func,
+};
+
+#ifdef CONFIG_PM_SLEEP
+static int i2c_pnx_controller_suspend(struct device *dev)
+{
+ struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(alg_data->clk);
+
+ return 0;
+}
+
+static int i2c_pnx_controller_resume(struct device *dev)
+{
+ struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev);
+
+ return clk_prepare_enable(alg_data->clk);
+}
+
+static SIMPLE_DEV_PM_OPS(i2c_pnx_pm,
+ i2c_pnx_controller_suspend, i2c_pnx_controller_resume);
+#define PNX_I2C_PM (&i2c_pnx_pm)
+#else
+#define PNX_I2C_PM NULL
+#endif
+
+static int i2c_pnx_probe(struct platform_device *pdev)
+{
+ unsigned long tmp;
+ int ret = 0;
+ struct i2c_pnx_algo_data *alg_data;
+ unsigned long freq;
+ struct resource *res;
+ u32 speed = I2C_PNX_SPEED_KHZ_DEFAULT * 1000;
+
+ alg_data = devm_kzalloc(&pdev->dev, sizeof(*alg_data), GFP_KERNEL);
+ if (!alg_data)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, alg_data);
+
+ alg_data->adapter.dev.parent = &pdev->dev;
+ alg_data->adapter.algo = &pnx_algorithm;
+ alg_data->adapter.algo_data = alg_data;
+ alg_data->adapter.nr = pdev->id;
+
+ alg_data->timeout = I2C_PNX_TIMEOUT_DEFAULT;
+#ifdef CONFIG_OF
+ alg_data->adapter.dev.of_node = of_node_get(pdev->dev.of_node);
+ if (pdev->dev.of_node) {
+ of_property_read_u32(pdev->dev.of_node, "clock-frequency",
+ &speed);
+ /*
+ * At this point, it is planned to add an OF timeout property.
+ * As soon as there is a consensus about how to call and handle
+ * this, sth. like the following can be put here:
+ *
+ * of_property_read_u32(pdev->dev.of_node, "timeout",
+ * &alg_data->timeout);
+ */
+ }
+#endif
+ alg_data->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(alg_data->clk))
+ return PTR_ERR(alg_data->clk);
+
+ timer_setup(&alg_data->mif.timer, i2c_pnx_timeout, 0);
+
+ snprintf(alg_data->adapter.name, sizeof(alg_data->adapter.name),
+ "%s", pdev->name);
+
+ /* Register I/O resource */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ alg_data->ioaddr = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(alg_data->ioaddr))
+ return PTR_ERR(alg_data->ioaddr);
+
+ ret = clk_prepare_enable(alg_data->clk);
+ if (ret)
+ return ret;
+
+ freq = clk_get_rate(alg_data->clk);
+
+ /*
+ * Clock Divisor High This value is the number of system clocks
+ * the serial clock (SCL) will be high.
+ * For example, if the system clock period is 50 ns and the maximum
+ * desired serial period is 10000 ns (100 kHz), then CLKHI would be
+ * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value
+ * programmed into CLKHI will vary from this slightly due to
+ * variations in the output pad's rise and fall times as well as
+ * the deglitching filter length.
+ */
+
+ tmp = (freq / speed) / 2 - 2;
+ if (tmp > 0x3FF)
+ tmp = 0x3FF;
+ iowrite32(tmp, I2C_REG_CKH(alg_data));
+ iowrite32(tmp, I2C_REG_CKL(alg_data));
+
+ iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data));
+ if (wait_reset(alg_data)) {
+ ret = -ENODEV;
+ goto out_clock;
+ }
+ init_completion(&alg_data->mif.complete);
+
+ alg_data->irq = platform_get_irq(pdev, 0);
+ if (alg_data->irq < 0) {
+ ret = alg_data->irq;
+ goto out_clock;
+ }
+ ret = devm_request_irq(&pdev->dev, alg_data->irq, i2c_pnx_interrupt,
+ 0, pdev->name, alg_data);
+ if (ret)
+ goto out_clock;
+
+ /* Register this adapter with the I2C subsystem */
+ ret = i2c_add_numbered_adapter(&alg_data->adapter);
+ if (ret < 0)
+ goto out_clock;
+
+ dev_dbg(&pdev->dev, "%s: Master at %pap, irq %d.\n",
+ alg_data->adapter.name, &res->start, alg_data->irq);
+
+ return 0;
+
+out_clock:
+ clk_disable_unprepare(alg_data->clk);
+ return ret;
+}
+
+static int i2c_pnx_remove(struct platform_device *pdev)
+{
+ struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&alg_data->adapter);
+ clk_disable_unprepare(alg_data->clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id i2c_pnx_of_match[] = {
+ { .compatible = "nxp,pnx-i2c" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, i2c_pnx_of_match);
+#endif
+
+static struct platform_driver i2c_pnx_driver = {
+ .driver = {
+ .name = "pnx-i2c",
+ .of_match_table = of_match_ptr(i2c_pnx_of_match),
+ .pm = PNX_I2C_PM,
+ },
+ .probe = i2c_pnx_probe,
+ .remove = i2c_pnx_remove,
+};
+
+static int __init i2c_adap_pnx_init(void)
+{
+ return platform_driver_register(&i2c_pnx_driver);
+}
+
+static void __exit i2c_adap_pnx_exit(void)
+{
+ platform_driver_unregister(&i2c_pnx_driver);
+}
+
+MODULE_AUTHOR("Vitaly Wool");
+MODULE_AUTHOR("Dennis Kovalev <source@mvista.com>");
+MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pnx-i2c");
+
+/* We need to make sure I2C is initialized before USB */
+subsys_initcall(i2c_adap_pnx_init);
+module_exit(i2c_adap_pnx_exit);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 19:36:12 +0000