| /* |
| * 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 <linux/slab.h> |
| #include <linux/hwspinlock.h> |
| #include <linux/i2c-omap.h> |
| #include <linux/pm_runtime.h> |
| #include <plat/omap_device.h> |
| #include <linux/pm_qos.h> |
| #include <linux/switch.h> |
| |
| /* I2C controller revisions */ |
| #define OMAP_I2C_OMAP1_REV_2 0x20 |
| |
| /* I2C controller revisions present on specific hardware */ |
| #define OMAP_I2C_REV_ON_2430 0x36 |
| #define OMAP_I2C_REV_ON_3430_3530 0x3C |
| #define OMAP_I2C_REV_ON_3630_4430 0x40 |
| |
| /* timeout waiting for the controller to respond */ |
| #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000)) |
| #define OMAP_I2C_MAX_TIMEOUTS (8) |
| |
| /* 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): */ |
| #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_TEST (2 << 12) /* Test mode select */ |
| #define OMAP_I2C_SYSTEST_TMODE_LOOP (3 << 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 */ |
| |
| /* 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 { |
| 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 */ |
| struct pm_qos_request pm_qos_request; |
| int (*get_context_loss_count)(struct device *dev); |
| u32 speed; /* Speed of bus in kHz */ |
| u32 dtrev; /* extra revision from DT */ |
| u32 flags; |
| u16 cmd_err; |
| u8 *buf; |
| u8 *regs; |
| size_t buf_len; |
| struct i2c_adapter adapter; |
| 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 */ |
| u16 iestate; /* Saved interrupt register */ |
| u16 pscstate; |
| u16 scllstate; |
| u16 sclhstate; |
| u16 bufstate; |
| u16 syscstate; |
| u16 westate; |
| u16 errata; |
| int dev_lost_count; |
| bool suspended; /* if true - I2C device |
| suspended and can't be |
| accessible*/ |
| struct switch_dev sdev; |
| int timeout_count; |
| }; |
| |
| 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 int omap_i2c_hwspinlock_lock(struct omap_i2c_dev *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev->dev); |
| struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data; |
| int ret = 0; |
| |
| if (pdata->hwspin_lock_timeout) { |
| ret = pdata->hwspin_lock_timeout(pdata->handle, 100); |
| if (ret != 0) |
| dev_err(&pdev->dev, "%s: TIMEDOUT: Failed to acquire" |
| " hwspinlock\n", __func__); |
| } |
| return ret; |
| } |
| |
| static void omap_i2c_hwspinlock_unlock(struct omap_i2c_dev *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev->dev); |
| struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data; |
| |
| if (pdata->hwspin_unlock) |
| pdata->hwspin_unlock(pdata->handle); |
| } |
| |
| static int omap_i2c_reset(struct omap_i2c_dev *dev) |
| { |
| unsigned long timeout; |
| if (dev->rev >= OMAP_I2C_OMAP1_REV_2) { |
| /* 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; |
| } |
| mdelay(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_3530) { |
| dev->syscstate = SYSC_AUTOIDLE_MASK; |
| dev->syscstate |= SYSC_ENAWAKEUP_MASK; |
| dev->syscstate |= (SYSC_IDLEMODE_SMART << |
| __ffs(SYSC_SIDLEMODE_MASK)); |
| dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK << |
| __ffs(SYSC_CLOCKACTIVITY_MASK)); |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, |
| dev->syscstate); |
| } |
| } |
| return 0; |
| } |
| |
| static int omap_i2c_init(struct omap_i2c_dev *dev) |
| { |
| u16 psc = 0, scll = 0, sclh = 0, buf = 0; |
| u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0; |
| unsigned long fclk_rate = 12000000; |
| unsigned long internal_clk = 0; |
| struct clk *fclk; |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); |
| |
| 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; |
| } |
| |
| /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */ |
| omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc); |
| |
| /* 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); |
| |
| if (dev->fifo_size) { |
| /* Note: setup required fifo size - 1. RTRSH and XTRSH */ |
| buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR | |
| (dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR; |
| omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf); |
| } |
| |
| /* Take the I2C module out of reset: */ |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); |
| |
| /* Enable interrupts */ |
| 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); |
| omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate); |
| 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; |
| omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, |
| dev->westate); |
| } |
| |
| if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) { |
| dev->pscstate = psc; |
| dev->scllstate = scll; |
| dev->sclhstate = sclh; |
| dev->bufstate = buf; |
| } |
| 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; |
| } |
| |
| /* |
| * Bus Clear |
| */ |
| static int omap_i2c_bus_clear(struct omap_i2c_dev *dev) |
| { |
| u16 w; |
| |
| /* |
| * Per the I2C specification, if we are stuck in a bus busy state |
| * we can attempt a bus clear to try and recover the bus by sending |
| * at least 9 clock pulses on SCL. Put the I2C in a test mode so it |
| * will output a continuous clock on SCL. |
| */ |
| w = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); |
| omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, (OMAP_I2C_SYSTEST_ST_EN |
| | OMAP_I2C_SYSTEST_TMODE_TEST)); |
| msleep(1); |
| omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, w); |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); |
| omap_i2c_reset(dev); |
| omap_i2c_init(dev); |
| return omap_i2c_wait_for_bb(dev); |
| } |
| |
| /* |
| * 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; |
| u8 *p; |
| |
| 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; |
| |
| 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; |
| |
| 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 (!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; |
| while ((omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) & |
| OMAP_I2C_CON_STT) == 0) { |
| |
| /* 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"); |
| goto controller_timedout; |
| } |
| 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); |
| dev->buf_len = 0; |
| if (timeout == 0) { |
| dev_err(dev->dev, "controller timed out\n"); |
| omap_i2c_init(dev); |
| goto controller_timedout; |
| } |
| |
| if (likely(!dev->cmd_err)) { |
| dev->timeout_count = OMAP_I2C_MAX_TIMEOUTS; |
| switch_set_state(&dev->sdev, 0); |
| return 0; |
| } |
| |
| /* We have an error */ |
| if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR | |
| OMAP_I2C_STAT_XUDF)) { |
| 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; |
| |
| controller_timedout: |
| dev->timeout_count -= 1; |
| dev_warn(dev->dev, |
| "omap i2c timeout. Remote i2c device address=0x%x, flags=0x%x", |
| msg->addr, msg->flags); |
| |
| dev_warn(dev->dev, "i2c command payload dump:"); |
| for (p=msg->buf; p<msg->buf+msg->len; p++) |
| dev_warn(dev->dev, "0x%x", *p); |
| |
| if (dev->timeout_count < 0) { |
| dev_warn(dev->dev, "Too many controller timeouts. Pulsing i2c error switch\n"); |
| switch_set_state(&dev->sdev, 0); |
| switch_set_state(&dev->sdev, 1); |
| dev->timeout_count = OMAP_I2C_MAX_TIMEOUTS; |
| } |
| return -ETIMEDOUT; |
| } |
| |
| |
| /* |
| * 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; |
| |
| /* Sanity check */ |
| if (!dev) { |
| dev_err(&adap->dev, "%s: invalid omap_i2c_dev\n", __func__); |
| return -EINVAL; |
| } |
| |
| if (dev->suspended) { |
| WARN(true, "%s: Access denied - device already suspended\n", |
| dev_name(dev->dev)); |
| return -EACCES; |
| } |
| |
| r = omap_i2c_hwspinlock_lock(dev); |
| /* To-Do: if we are unable to acquire the lock, we must |
| try to recover somehow */ |
| if (r != 0) |
| return r; |
| |
| r = pm_runtime_get_sync(dev->dev); |
| if (r < 0) { |
| goto err_pm; |
| } |
| |
| /* We have the bus, enable IRQ */ |
| enable_irq(dev->irq); |
| |
| r = omap_i2c_wait_for_bb(dev); |
| if (r < 0) |
| r = omap_i2c_bus_clear(dev); |
| if (r < 0) |
| goto out; |
| |
| /* |
| * When waiting for completion of a i2c transfer, we need to |
| * set a wake up latency constraint for the MPU. This is to |
| * ensure quick enough wakeup from idle, when transfer |
| * completes. |
| */ |
| if (dev->latency) |
| pm_qos_update_request(&dev->pm_qos_request, dev->latency); |
| |
| for (i = 0; i < num; i++) { |
| r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1))); |
| if (r != 0) |
| break; |
| } |
| |
| if (dev->latency) |
| pm_qos_update_request(&dev->pm_qos_request, |
| PM_QOS_DEFAULT_VALUE); |
| |
| if (r == 0) |
| r = num; |
| |
| omap_i2c_wait_for_bb(dev); |
| out: |
| disable_irq(dev->irq); |
| err_pm: |
| pm_runtime_put_sync(dev->dev); |
| omap_i2c_hwspinlock_unlock(dev); |
| return r; |
| } |
| |
| static u32 |
| omap_i2c_func(struct i2c_adapter *adap) |
| { |
| return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); |
| } |
| |
| 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, u16 *stat, int *err) |
| { |
| unsigned long timeout = 10000; |
| |
| while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) { |
| if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { |
| omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY | |
| OMAP_I2C_STAT_XDR)); |
| return -ETIMEDOUT; |
| } |
| |
| cpu_relax(); |
| *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); |
| } |
| |
| if (!timeout) { |
| dev_err(dev->dev, "timeout waiting on XUDF bit\n"); |
| return 0; |
| } |
| |
| *err |= OMAP_I2C_STAT_XUDF; |
| return 0; |
| } |
| |
| static int process_read_rdy(struct omap_i2c_dev *dev, u16 stat) |
| { |
| u8 num_bytes = 1; |
| u16 w; |
| |
| if (dev->errata & I2C_OMAP_ERRATA_I207) |
| i2c_omap_errata_i207(dev, stat); |
| |
| if (dev->fifo_size) { |
| if (stat & OMAP_I2C_STAT_RRDY) |
| num_bytes = dev->fifo_size; |
| else /* read RXSTAT on RDR interrupt */ |
| num_bytes = (omap_i2c_read_reg(dev, |
| OMAP_I2C_BUFSTAT_REG) >> 8) & 0x3F; |
| } |
| while (num_bytes) { |
| num_bytes--; |
| w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG); |
| if (dev->buf_len) { |
| *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) { |
| 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"); |
| return -EIO; |
| } |
| } |
| return 0; |
| } |
| |
| static irqreturn_t |
| omap_i2c_isr(int this_irq, void *dev_id) |
| { |
| struct omap_i2c_dev *dev = dev_id; |
| u16 bits; |
| u16 stat, w; |
| int err, count = 0; |
| |
| if (pm_runtime_suspended(dev->dev)) |
| return IRQ_NONE; |
| |
| bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); |
| while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) { |
| 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; |
| } |
| |
| err = 0; |
| complete: |
| /* |
| * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be |
| * acked after the data operation is complete. |
| * Ref: TRM SWPU114Q Figure 18-31 |
| */ |
| omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat & |
| ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR | |
| OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)); |
| |
| if (stat & OMAP_I2C_STAT_NACK) |
| err |= OMAP_I2C_STAT_NACK; |
| |
| if (stat & OMAP_I2C_STAT_AL) { |
| dev_err(dev->dev, "Arbitration lost\n"); |
| err |= OMAP_I2C_STAT_AL; |
| } |
| /* |
| * ProDB0017052: Clear ARDY bit twice |
| */ |
| if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK | |
| OMAP_I2C_STAT_AL)) { |
| omap_i2c_ack_stat(dev, stat & |
| (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR | |
| OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR | |
| OMAP_I2C_STAT_ARDY)); |
| omap_i2c_complete_cmd(dev, err); |
| return IRQ_HANDLED; |
| } |
| if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) { |
| if (process_read_rdy(dev, stat) == -EIO) |
| break; |
| |
| omap_i2c_ack_stat(dev, |
| stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)); |
| continue; |
| } |
| 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 /* read TXSTAT on XDR interrupt */ |
| num_bytes = omap_i2c_read_reg(dev, |
| OMAP_I2C_BUFSTAT_REG) |
| & 0x3F; |
| } |
| while (num_bytes) { |
| num_bytes--; |
| w = 0; |
| if (dev->buf_len) { |
| 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) { |
| 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; |
| } |
| |
| if ((dev->errata & I2C_OMAP_ERRATA_I462) && |
| errata_omap3_i462(dev, &stat, &err)) |
| goto complete; |
| |
| 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) { |
| dev_err(dev->dev, "Receive overrun\n"); |
| dev->cmd_err |= OMAP_I2C_STAT_ROVR; |
| } |
| if (stat & OMAP_I2C_STAT_XUDF) { |
| dev_err(dev->dev, "Transmit underflow\n"); |
| dev->cmd_err |= OMAP_I2C_STAT_XUDF; |
| } |
| } |
| |
| return count ? IRQ_HANDLED : IRQ_NONE; |
| } |
| |
| 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_APPLY_ERRATA_I207 | |
| OMAP_I2C_FLAG_RESET_REGS_POSTIDLE | |
| 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 |
| |
| static int __devinit |
| omap_i2c_probe(struct platform_device *pdev) |
| { |
| struct omap_i2c_dev *dev; |
| struct i2c_adapter *adap; |
| struct resource *mem, *irq; |
| 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; |
| irq_handler_t isr; |
| int r; |
| |
| /* 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_resource(pdev, IORESOURCE_IRQ, 0); |
| if (!irq) { |
| dev_err(&pdev->dev, "no irq resource?\n"); |
| return -ENODEV; |
| } |
| |
| dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL); |
| if (!dev) { |
| dev_err(&pdev->dev, "Memory 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->dtrev = pdata->rev; |
| 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->get_context_loss_count = pdata->get_context_loss_count; |
| dev->dtrev = pdata->rev; |
| } |
| |
| dev->dev = &pdev->dev; |
| dev->irq = irq->start; |
| |
| platform_set_drvdata(pdev, dev); |
| init_completion(&dev->cmd_complete); |
| |
| dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3; |
| |
| if (dev->dtrev == OMAP_I2C_IP_VERSION_2) |
| dev->regs = (u8 *)reg_map_ip_v2; |
| else |
| dev->regs = (u8 *)reg_map_ip_v1; |
| |
| pm_runtime_enable(dev->dev); |
| r = pm_runtime_get_sync(dev->dev); |
| if (r < 0) |
| return -ENOMEM; |
| |
| dev->pm_qos_request.dev = dev->dev; |
| pm_qos_add_request(&dev->pm_qos_request, |
| PM_QOS_CPU_DMA_LATENCY, |
| PM_QOS_DEFAULT_VALUE); |
| |
| dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff; |
| |
| dev->errata = 0; |
| |
| if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207) |
| 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_4430) |
| dev->b_hw = 0; /* Disable hardware fixes */ |
| else |
| dev->b_hw = 1; /* Enable hardware fixes */ |
| |
| /* calculate wakeup latency constraint */ |
| dev->latency = (1000000 * dev->fifo_size) / |
| (1000 * dev->speed / 8); |
| } |
| |
| /* reset ASAP, clearing any IRQs */ |
| omap_i2c_init(dev); |
| |
| isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr : |
| omap_i2c_isr; |
| r = request_irq(dev->irq, isr, 0, pdev->name, dev); |
| |
| /* We enable IRQ only when request for I2C from master */ |
| disable_irq(dev->irq); |
| |
| if (r) { |
| dev_err(dev->dev, "failure requesting irq %i\n", dev->irq); |
| goto err_unuse_clocks; |
| } |
| |
| dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", pdev->id, |
| dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed); |
| |
| 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_free_irq; |
| } |
| |
| of_i2c_register_devices(adap); |
| |
| pm_runtime_put(dev->dev); |
| |
| /* create a switch device to notify userspace in case i2c error occurs */ |
| dev->sdev.name = kasprintf(GFP_KERNEL, "%s.%d-%s", "i2c", pdev->id, "error"); |
| r = switch_dev_register(&dev->sdev); |
| if (r) { |
| dev_err(dev->dev, "error registering switch device: %d\n", r); |
| } |
| |
| return 0; |
| |
| err_free_irq: |
| free_irq(dev->irq, dev); |
| err_unuse_clocks: |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); |
| pm_runtime_put(dev->dev); |
| pm_runtime_disable(&pdev->dev); |
| platform_set_drvdata(pdev, NULL); |
| pm_qos_remove_request(&dev->pm_qos_request); |
| |
| return r; |
| } |
| |
| static int __devexit omap_i2c_remove(struct platform_device *pdev) |
| { |
| struct omap_i2c_dev *dev = platform_get_drvdata(pdev); |
| int ret; |
| |
| platform_set_drvdata(pdev, NULL); |
| |
| free_irq(dev->irq, dev); |
| i2c_del_adapter(&dev->adapter); |
| ret = pm_runtime_get_sync(&pdev->dev); |
| if (ret < 0) |
| return ret; |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); |
| pm_runtime_put(&pdev->dev); |
| pm_runtime_disable(&pdev->dev); |
| pm_qos_remove_request(&dev->pm_qos_request); |
| switch_dev_unregister(&dev->sdev); |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| #ifdef CONFIG_PM_RUNTIME |
| static void omap_i2c_restore(struct omap_i2c_dev *dev) |
| { |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); |
| omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate); |
| omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate); |
| omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate); |
| omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, dev->bufstate); |
| omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate); |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); |
| |
| } |
| 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); |
| u16 iv; |
| |
| if (_dev->get_context_loss_count) |
| _dev->dev_lost_count = _dev->get_context_loss_count(dev); |
| |
| _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) { |
| 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 */ |
| 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); |
| int loss_cnt; |
| |
| if (!(_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)) |
| return 0; |
| |
| if (_dev->get_context_loss_count) { |
| loss_cnt = _dev->get_context_loss_count(dev); |
| if (_dev->dev_lost_count != loss_cnt) |
| omap_i2c_restore(_dev); |
| } |
| |
| /* |
| * 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); |
| |
| return 0; |
| } |
| #endif /* CONFIG_PM_RUNTIME */ |
| |
| static int omap_i2c_suspend(struct device *dev) |
| { |
| int ret; |
| |
| /* |
| * Enable I2C device, so it will be accessible during |
| * later stages of suspending when device Runtime PM is disabled. |
| * I2C device will be turned off at "noirq" suspend stage. |
| */ |
| if (atomic_read(&dev->power.usage_count) > 1) { |
| dev_info(dev, |
| "active I2C transaction detected - suspend aborted\n"); |
| return -EBUSY; |
| } |
| ret = pm_runtime_resume(dev); |
| if (ret < 0) |
| return ret; |
| return 0; |
| } |
| |
| static int omap_i2c_suspend_noirq(struct device *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct omap_i2c_dev *_dev = platform_get_drvdata(pdev); |
| |
| /* |
| * Below code is needed only to ensure that there are no |
| * activities on I2C bus. if at this moment any driver |
| * is trying to use I2C bus - this is the BUG and this |
| * may cause system crash. |
| * |
| * So forbid access to I2C device using _dev->suspended flag. |
| */ |
| |
| i2c_lock_adapter(&_dev->adapter); |
| |
| /* Check for active I2C transaction */ |
| if (atomic_read(&dev->power.usage_count) > 1) { |
| dev_info(dev, |
| "active I2C transaction detected - suspend aborted\n"); |
| return -EBUSY; |
| } |
| |
| _dev->suspended = true; |
| |
| i2c_unlock_adapter(&_dev->adapter); |
| |
| /* |
| * I2C device will be turned off by omap_device framework |
| * on exit from .suspend_noirq() callback. |
| * So, it will not be accessible any more. |
| */ |
| return 0; |
| } |
| |
| static int omap_i2c_resume_noirq(struct device *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct omap_i2c_dev *_dev = platform_get_drvdata(pdev); |
| |
| /* |
| * I2C device has been turned on already by omap_device framework |
| * unconditionally. So, it will be accessible during earlier |
| * stages of resuming when device Runtime PM is disabled |
| */ |
| |
| /* Allow access to I2C bus*/ |
| i2c_lock_adapter(&_dev->adapter); |
| _dev->suspended = false; |
| i2c_unlock_adapter(&_dev->adapter); |
| |
| return 0; |
| } |
| |
| static struct dev_pm_ops omap_i2c_pm_ops = { |
| .suspend_noirq = omap_i2c_suspend_noirq, |
| .resume_noirq = omap_i2c_resume_noirq, |
| SET_SYSTEM_SLEEP_PM_OPS(omap_i2c_suspend, NULL) |
| 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 = __devexit_p(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"); |