diff options
Diffstat (limited to 'kernel/drivers/i2c/busses/i2c-pnx.c')
-rw-r--r-- | kernel/drivers/i2c/busses/i2c-pnx.c | 778 |
1 files changed, 778 insertions, 0 deletions
diff --git a/kernel/drivers/i2c/busses/i2c-pnx.c b/kernel/drivers/i2c/busses/i2c-pnx.c new file mode 100644 index 000000000..e814a36d9 --- /dev/null +++ b/kernel/drivers/i2c/busses/i2c-pnx.c @@ -0,0 +1,778 @@ +/* + * 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/i2c-pnx.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 + +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; + timer->data = (unsigned long)alg_data; + + add_timer(timer); +} + +/** + * i2c_pnx_start - start a device + * @slave_addr: slave address + * @adap: pointer to adapter 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 + * @adap: pointer to I2C adapter 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 + * @adap: pointer to I2C adapter 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 + * @adap: pointer to I2C adapter 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(unsigned long data) +{ + struct i2c_pnx_algo_data *alg_data = (struct i2c_pnx_algo_data *)data; + 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 = ioread32(I2C_REG_STS(alg_data)); + + 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 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(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_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); + + init_timer(&alg_data->mif.timer); + alg_data->mif.timer.function = i2c_pnx_timeout; + alg_data->mif.timer.data = (unsigned long)alg_data; + + 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_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) { + dev_err(&pdev->dev, "Failed to get IRQ from platform resource\n"); + 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) { + dev_err(&pdev->dev, "I2C: Failed to add bus\n"); + goto out_clock; + } + + dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n", + alg_data->adapter.name, res->start, alg_data->irq); + + return 0; + +out_clock: + clk_disable(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(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, 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); |