| /* |
| * 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. |
| */ |
| |
| #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_device.h> |
| #include <linux/slab.h> |
| #include <linux/i2c-omap.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/pinctrl/consumer.h> |
| |
| /* I2C controller revisions */ |
| #define OMAP_I2C_OMAP1_REV_2 0x20 |
| |
| /* I2C controller revisions present on specific hardware */ |
| #define OMAP_I2C_REV_ON_2430 0x00000036 |
| #define OMAP_I2C_REV_ON_3430_3530 0x0000003C |
| #define OMAP_I2C_REV_ON_3630 0x00000040 |
| #define OMAP_I2C_REV_ON_4430_PLUS 0x50400002 |
| |
| /* timeout waiting for the controller to respond */ |
| #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000)) |
| |
| /* timeout for pm runtime autosuspend */ |
| #define OMAP_I2C_PM_TIMEOUT 1000 /* ms */ |
| |
| /* timeout for making decision on bus free status */ |
| #define OMAP_I2C_BUS_FREE_TIMEOUT (msecs_to_jiffies(10)) |
| |
| /* 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_BF (1 << 8) /* Bus Free */ |
| #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_SHIFT (12) /* Test mode select */ |
| /* Functional mode */ |
| #define OMAP_I2C_SYSTEST_SCL_I_FUNC (1 << 8) /* SCL line input value */ |
| #define OMAP_I2C_SYSTEST_SCL_O_FUNC (1 << 7) /* SCL line output value */ |
| #define OMAP_I2C_SYSTEST_SDA_I_FUNC (1 << 6) /* SDA line input value */ |
| #define OMAP_I2C_SYSTEST_SDA_O_FUNC (1 << 5) /* SDA line output value */ |
| /* SDA/SCL IO mode */ |
| #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_SYSSTATUS bit definitions */ |
| #define SYSS_RESETDONE_MASK (1 << 0) |
| |
| /* OCP_SYSCONFIG bit definitions */ |
| #define SYSC_CLOCKACTIVITY_MASK (0x3 << 8) |
| #define SYSC_SIDLEMODE_MASK (0x3 << 3) |
| #define SYSC_ENAWAKEUP_MASK (1 << 2) |
| #define SYSC_SOFTRESET_MASK (1 << 1) |
| #define SYSC_AUTOIDLE_MASK (1 << 0) |
| |
| #define SYSC_IDLEMODE_SMART 0x2 |
| #define SYSC_CLOCKACTIVITY_FCLK 0x2 |
| |
| /* Errata definitions */ |
| #define I2C_OMAP_ERRATA_I207 (1 << 0) |
| #define I2C_OMAP_ERRATA_I462 (1 << 1) |
| |
| #define OMAP_I2C_IP_V2_INTERRUPTS_MASK 0x6FFF |
| |
| struct omap_i2c_dev { |
| spinlock_t lock; /* IRQ synchronization */ |
| struct device *dev; |
| void __iomem *base; /* virtual */ |
| int irq; |
| int reg_shift; /* bit shift for I2C register addresses */ |
| struct completion cmd_complete; |
| struct resource *ioarea; |
| u32 latency; /* maximum mpu wkup latency */ |
| void (*set_mpu_wkup_lat)(struct device *dev, |
| long latency); |
| u32 speed; /* Speed of bus in kHz */ |
| u32 flags; |
| u16 scheme; |
| u16 cmd_err; |
| u8 *buf; |
| u8 *regs; |
| size_t buf_len; |
| struct i2c_adapter adapter; |
| u8 threshold; |
| u8 fifo_size; /* use as flag and value |
| * fifo_size==0 implies no fifo |
| * if set, should be trsh+1 |
| */ |
| u32 rev; |
| unsigned b_hw:1; /* bad h/w fixes */ |
| unsigned bb_valid:1; /* true when BB-bit reflects |
| * the I2C bus state |
| */ |
| unsigned receiver:1; /* true when we're in receiver mode */ |
| u16 iestate; /* Saved interrupt register */ |
| u16 pscstate; |
| u16 scllstate; |
| u16 sclhstate; |
| u16 syscstate; |
| u16 westate; |
| u16 errata; |
| }; |
| |
| 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) |
| { |
| writew_relaxed(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 readw_relaxed(i2c_dev->base + |
| (i2c_dev->regs[reg] << i2c_dev->reg_shift)); |
| } |
| |
| static void __omap_i2c_init(struct omap_i2c_dev *dev) |
| { |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); |
| |
| /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */ |
| omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate); |
| |
| /* SCL low and high time values */ |
| omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate); |
| omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate); |
| if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) |
| omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate); |
| |
| /* Take the I2C module out of reset: */ |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); |
| |
| /* |
| * NOTE: right after setting CON_EN, STAT_BB could be 0 while the |
| * bus is busy. It will be changed to 1 on the next IP FCLK clock. |
| * udelay(1) will be enough to fix that. |
| */ |
| |
| /* |
| * Don't write to this register if the IE state is 0 as it can |
| * cause deadlock. |
| */ |
| if (dev->iestate) |
| omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate); |
| } |
| |
| static int omap_i2c_reset(struct omap_i2c_dev *dev) |
| { |
| unsigned long timeout; |
| u16 sysc; |
| |
| if (dev->rev >= OMAP_I2C_OMAP1_REV_2) { |
| sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG); |
| |
| /* Disable I2C controller before soft reset */ |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, |
| omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) & |
| ~(OMAP_I2C_CON_EN)); |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK); |
| /* For some reason we need to set the EN bit before the |
| * reset done bit gets set. */ |
| timeout = jiffies + OMAP_I2C_TIMEOUT; |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); |
| while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) & |
| SYSS_RESETDONE_MASK)) { |
| if (time_after(jiffies, timeout)) { |
| dev_warn(dev->dev, "timeout waiting " |
| "for controller reset\n"); |
| return -ETIMEDOUT; |
| } |
| msleep(1); |
| } |
| |
| /* SYSC register is cleared by the reset; rewrite it */ |
| omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc); |
| |
| if (dev->rev > OMAP_I2C_REV_ON_3430_3530) { |
| /* Schedule I2C-bus monitoring on the next transfer */ |
| dev->bb_valid = 0; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int omap_i2c_init(struct omap_i2c_dev *dev) |
| { |
| u16 psc = 0, scll = 0, sclh = 0; |
| u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0; |
| unsigned long fclk_rate = 12000000; |
| unsigned long internal_clk = 0; |
| struct clk *fclk; |
| |
| if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) { |
| /* |
| * Enabling all wakup sources to stop I2C freezing on |
| * WFI instruction. |
| * REVISIT: Some wkup sources might not be needed. |
| */ |
| dev->westate = OMAP_I2C_WE_ALL; |
| } |
| |
| if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) { |
| /* |
| * The I2C functional clock is the armxor_ck, so there's |
| * no need to get "armxor_ck" separately. Now, if OMAP2420 |
| * always returns 12MHz for the functional clock, we can |
| * do this bit unconditionally. |
| */ |
| fclk = clk_get(dev->dev, "fck"); |
| fclk_rate = clk_get_rate(fclk); |
| clk_put(fclk); |
| |
| /* TRM for 5912 says the I2C clock must be prescaled to be |
| * between 7 - 12 MHz. The XOR input clock is typically |
| * 12, 13 or 19.2 MHz. So we should have code that produces: |
| * |
| * XOR MHz Divider Prescaler |
| * 12 1 0 |
| * 13 2 1 |
| * 19.2 2 1 |
| */ |
| if (fclk_rate > 12000000) |
| psc = fclk_rate / 12000000; |
| } |
| |
| if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) { |
| |
| /* |
| * HSI2C controller internal clk rate should be 19.2 Mhz for |
| * HS and for all modes on 2430. On 34xx we can use lower rate |
| * to get longer filter period for better noise suppression. |
| * The filter is iclk (fclk for HS) period. |
| */ |
| if (dev->speed > 400 || |
| dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK) |
| internal_clk = 19200; |
| else if (dev->speed > 100) |
| internal_clk = 9600; |
| else |
| internal_clk = 4000; |
| fclk = clk_get(dev->dev, "fck"); |
| fclk_rate = clk_get_rate(fclk) / 1000; |
| clk_put(fclk); |
| |
| /* Compute prescaler divisor */ |
| psc = fclk_rate / internal_clk; |
| psc = psc - 1; |
| |
| /* If configured for High Speed */ |
| if (dev->speed > 400) { |
| unsigned long scl; |
| |
| /* For first phase of HS mode */ |
| scl = internal_clk / 400; |
| fsscll = scl - (scl / 3) - 7; |
| fssclh = (scl / 3) - 5; |
| |
| /* For second phase of HS mode */ |
| scl = fclk_rate / dev->speed; |
| hsscll = scl - (scl / 3) - 7; |
| hssclh = (scl / 3) - 5; |
| } else if (dev->speed > 100) { |
| unsigned long scl; |
| |
| /* Fast mode */ |
| scl = internal_clk / dev->speed; |
| fsscll = scl - (scl / 3) - 7; |
| fssclh = (scl / 3) - 5; |
| } else { |
| /* Standard mode */ |
| fsscll = internal_clk / (dev->speed * 2) - 7; |
| fssclh = internal_clk / (dev->speed * 2) - 5; |
| } |
| scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll; |
| sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh; |
| } else { |
| /* Program desired operating rate */ |
| fclk_rate /= (psc + 1) * 1000; |
| if (psc > 2) |
| psc = 2; |
| scll = fclk_rate / (dev->speed * 2) - 7 + psc; |
| sclh = fclk_rate / (dev->speed * 2) - 7 + psc; |
| } |
| |
| dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY | |
| OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK | |
| OMAP_I2C_IE_AL) | ((dev->fifo_size) ? |
| (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0); |
| |
| dev->pscstate = psc; |
| dev->scllstate = scll; |
| dev->sclhstate = sclh; |
| |
| if (dev->rev <= OMAP_I2C_REV_ON_3430_3530) { |
| /* Not implemented */ |
| dev->bb_valid = 1; |
| } |
| |
| __omap_i2c_init(dev); |
| |
| return 0; |
| } |
| |
| /* |
| * Waiting on Bus Busy |
| */ |
| static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev) |
| { |
| unsigned long timeout; |
| |
| timeout = jiffies + OMAP_I2C_TIMEOUT; |
| while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) { |
| if (time_after(jiffies, timeout)) |
| return i2c_recover_bus(&dev->adapter); |
| msleep(1); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Wait while BB-bit doesn't reflect the I2C bus state |
| * |
| * In a multimaster environment, after IP software reset, BB-bit value doesn't |
| * correspond to the current bus state. It may happen what BB-bit will be 0, |
| * while the bus is busy due to another I2C master activity. |
| * Here are BB-bit values after reset: |
| * SDA SCL BB NOTES |
| * 0 0 0 1, 2 |
| * 1 0 0 1, 2 |
| * 0 1 1 |
| * 1 1 0 3 |
| * Later, if IP detect SDA=0 and SCL=1 (ACK) or SDA 1->0 while SCL=1 (START) |
| * combinations on the bus, it set BB-bit to 1. |
| * If IP detect SDA 0->1 while SCL=1 (STOP) combination on the bus, |
| * it set BB-bit to 0 and BF to 1. |
| * BB and BF bits correctly tracks the bus state while IP is suspended |
| * BB bit became valid on the next FCLK clock after CON_EN bit set |
| * |
| * NOTES: |
| * 1. Any transfer started when BB=0 and bus is busy wouldn't be |
| * completed by IP and results in controller timeout. |
| * 2. Any transfer started when BB=0 and SCL=0 results in IP |
| * starting to drive SDA low. In that case IP corrupt data |
| * on the bus. |
| * 3. Any transfer started in the middle of another master's transfer |
| * results in unpredictable results and data corruption |
| */ |
| static int omap_i2c_wait_for_bb_valid(struct omap_i2c_dev *dev) |
| { |
| unsigned long bus_free_timeout = 0; |
| unsigned long timeout; |
| int bus_free = 0; |
| u16 stat, systest; |
| |
| if (dev->bb_valid) |
| return 0; |
| |
| timeout = jiffies + OMAP_I2C_TIMEOUT; |
| while (1) { |
| stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); |
| /* |
| * We will see BB or BF event in a case IP had detected any |
| * activity on the I2C bus. Now IP correctly tracks the bus |
| * state. BB-bit value is valid. |
| */ |
| if (stat & (OMAP_I2C_STAT_BB | OMAP_I2C_STAT_BF)) |
| break; |
| |
| /* |
| * Otherwise, we must look signals on the bus to make |
| * the right decision. |
| */ |
| systest = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); |
| if ((systest & OMAP_I2C_SYSTEST_SCL_I_FUNC) && |
| (systest & OMAP_I2C_SYSTEST_SDA_I_FUNC)) { |
| if (!bus_free) { |
| bus_free_timeout = jiffies + |
| OMAP_I2C_BUS_FREE_TIMEOUT; |
| bus_free = 1; |
| } |
| |
| /* |
| * SDA and SCL lines was high for 10 ms without bus |
| * activity detected. The bus is free. Consider |
| * BB-bit value is valid. |
| */ |
| if (time_after(jiffies, bus_free_timeout)) |
| break; |
| } else { |
| bus_free = 0; |
| } |
| |
| if (time_after(jiffies, timeout)) { |
| dev_warn(dev->dev, "timeout waiting for bus ready\n"); |
| return -ETIMEDOUT; |
| } |
| |
| msleep(1); |
| } |
| |
| dev->bb_valid = 1; |
| return 0; |
| } |
| |
| static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx) |
| { |
| u16 buf; |
| |
| if (dev->flags & OMAP_I2C_FLAG_NO_FIFO) |
| return; |
| |
| /* |
| * Set up notification threshold based on message size. We're doing |
| * this to try and avoid draining feature as much as possible. Whenever |
| * we have big messages to transfer (bigger than our total fifo size) |
| * then we might use draining feature to transfer the remaining bytes. |
| */ |
| |
| dev->threshold = clamp(size, (u8) 1, dev->fifo_size); |
| |
| buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG); |
| |
| if (is_rx) { |
| /* Clear RX Threshold */ |
| buf &= ~(0x3f << 8); |
| buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR; |
| } else { |
| /* Clear TX Threshold */ |
| buf &= ~0x3f; |
| buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR; |
| } |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf); |
| |
| if (dev->rev < OMAP_I2C_REV_ON_3630) |
| dev->b_hw = 1; /* Enable hardware fixes */ |
| |
| /* calculate wakeup latency constraint for MPU */ |
| if (dev->set_mpu_wkup_lat != NULL) |
| dev->latency = (1000000 * dev->threshold) / |
| (1000 * dev->speed / 8); |
| } |
| |
| /* |
| * Low level master read/write transaction. |
| */ |
| static int omap_i2c_xfer_msg(struct i2c_adapter *adap, |
| struct i2c_msg *msg, int stop) |
| { |
| struct omap_i2c_dev *dev = i2c_get_adapdata(adap); |
| unsigned long timeout; |
| u16 w; |
| |
| dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n", |
| msg->addr, msg->len, msg->flags, stop); |
| |
| if (msg->len == 0) |
| return -EINVAL; |
| |
| dev->receiver = !!(msg->flags & I2C_M_RD); |
| omap_i2c_resize_fifo(dev, msg->len, dev->receiver); |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr); |
| |
| /* REVISIT: Could the STB bit of I2C_CON be used with probing? */ |
| dev->buf = msg->buf; |
| dev->buf_len = msg->len; |
| |
| /* make sure writes to dev->buf_len are ordered */ |
| barrier(); |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len); |
| |
| /* Clear the FIFO Buffers */ |
| w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG); |
| w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR; |
| omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w); |
| |
| reinit_completion(&dev->cmd_complete); |
| dev->cmd_err = 0; |
| |
| w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT; |
| |
| /* High speed configuration */ |
| if (dev->speed > 400) |
| w |= OMAP_I2C_CON_OPMODE_HS; |
| |
| if (msg->flags & I2C_M_STOP) |
| stop = 1; |
| if (msg->flags & I2C_M_TEN) |
| w |= OMAP_I2C_CON_XA; |
| if (!(msg->flags & I2C_M_RD)) |
| w |= OMAP_I2C_CON_TRX; |
| |
| if (!dev->b_hw && stop) |
| w |= OMAP_I2C_CON_STP; |
| /* |
| * NOTE: STAT_BB bit could became 1 here if another master occupy |
| * the bus. IP successfully complete transfer when the bus will be |
| * free again (BB reset to 0). |
| */ |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w); |
| |
| /* |
| * Don't write stt and stp together on some hardware. |
| */ |
| if (dev->b_hw && stop) { |
| unsigned long delay = jiffies + OMAP_I2C_TIMEOUT; |
| u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG); |
| while (con & OMAP_I2C_CON_STT) { |
| con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG); |
| |
| /* Let the user know if i2c is in a bad state */ |
| if (time_after(jiffies, delay)) { |
| dev_err(dev->dev, "controller timed out " |
| "waiting for start condition to finish\n"); |
| return -ETIMEDOUT; |
| } |
| cpu_relax(); |
| } |
| |
| w |= OMAP_I2C_CON_STP; |
| w &= ~OMAP_I2C_CON_STT; |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w); |
| } |
| |
| /* |
| * REVISIT: We should abort the transfer on signals, but the bus goes |
| * into arbitration and we're currently unable to recover from it. |
| */ |
| timeout = wait_for_completion_timeout(&dev->cmd_complete, |
| OMAP_I2C_TIMEOUT); |
| if (timeout == 0) { |
| dev_err(dev->dev, "controller timed out\n"); |
| omap_i2c_reset(dev); |
| __omap_i2c_init(dev); |
| return -ETIMEDOUT; |
| } |
| |
| if (likely(!dev->cmd_err)) |
| return 0; |
| |
| /* We have an error */ |
| if (dev->cmd_err & (OMAP_I2C_STAT_ROVR | OMAP_I2C_STAT_XUDF)) { |
| omap_i2c_reset(dev); |
| __omap_i2c_init(dev); |
| return -EIO; |
| } |
| |
| if (dev->cmd_err & OMAP_I2C_STAT_AL) |
| return -EAGAIN; |
| |
| if (dev->cmd_err & OMAP_I2C_STAT_NACK) { |
| if (msg->flags & I2C_M_IGNORE_NAK) |
| return 0; |
| |
| w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG); |
| w |= OMAP_I2C_CON_STP; |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w); |
| return -EREMOTEIO; |
| } |
| return -EIO; |
| } |
| |
| |
| /* |
| * Prepare controller for a transaction and call omap_i2c_xfer_msg |
| * to do the work during IRQ processing. |
| */ |
| static int |
| omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) |
| { |
| struct omap_i2c_dev *dev = i2c_get_adapdata(adap); |
| int i; |
| int r; |
| |
| r = pm_runtime_get_sync(dev->dev); |
| if (r < 0) |
| goto out; |
| |
| r = omap_i2c_wait_for_bb_valid(dev); |
| if (r < 0) |
| goto out; |
| |
| r = omap_i2c_wait_for_bb(dev); |
| if (r < 0) |
| goto out; |
| |
| if (dev->set_mpu_wkup_lat != NULL) |
| dev->set_mpu_wkup_lat(dev->dev, dev->latency); |
| |
| for (i = 0; i < num; i++) { |
| r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1))); |
| if (r != 0) |
| break; |
| } |
| |
| if (r == 0) |
| r = num; |
| |
| omap_i2c_wait_for_bb(dev); |
| |
| if (dev->set_mpu_wkup_lat != NULL) |
| dev->set_mpu_wkup_lat(dev->dev, -1); |
| |
| out: |
| pm_runtime_mark_last_busy(dev->dev); |
| pm_runtime_put_autosuspend(dev->dev); |
| return r; |
| } |
| |
| static u32 |
| omap_i2c_func(struct i2c_adapter *adap) |
| { |
| return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | |
| I2C_FUNC_PROTOCOL_MANGLING; |
| } |
| |
| static inline void |
| omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err) |
| { |
| dev->cmd_err |= err; |
| complete(&dev->cmd_complete); |
| } |
| |
| static inline void |
| omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat) |
| { |
| omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat); |
| } |
| |
| static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat) |
| { |
| /* |
| * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8) |
| * Not applicable for OMAP4. |
| * Under certain rare conditions, RDR could be set again |
| * when the bus is busy, then ignore the interrupt and |
| * clear the interrupt. |
| */ |
| if (stat & OMAP_I2C_STAT_RDR) { |
| /* Step 1: If RDR is set, clear it */ |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR); |
| |
| /* Step 2: */ |
| if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) |
| & OMAP_I2C_STAT_BB)) { |
| |
| /* Step 3: */ |
| if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) |
| & OMAP_I2C_STAT_RDR) { |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR); |
| dev_dbg(dev->dev, "RDR when bus is busy.\n"); |
| } |
| |
| } |
| } |
| } |
| |
| /* rev1 devices are apparently only on some 15xx */ |
| #ifdef CONFIG_ARCH_OMAP15XX |
| |
| static irqreturn_t |
| omap_i2c_omap1_isr(int this_irq, void *dev_id) |
| { |
| struct omap_i2c_dev *dev = dev_id; |
| u16 iv, w; |
| |
| if (pm_runtime_suspended(dev->dev)) |
| return IRQ_NONE; |
| |
| iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); |
| switch (iv) { |
| case 0x00: /* None */ |
| break; |
| case 0x01: /* Arbitration lost */ |
| dev_err(dev->dev, "Arbitration lost\n"); |
| omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL); |
| break; |
| case 0x02: /* No acknowledgement */ |
| omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK); |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP); |
| break; |
| case 0x03: /* Register access ready */ |
| omap_i2c_complete_cmd(dev, 0); |
| break; |
| case 0x04: /* Receive data ready */ |
| if (dev->buf_len) { |
| w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG); |
| *dev->buf++ = w; |
| dev->buf_len--; |
| if (dev->buf_len) { |
| *dev->buf++ = w >> 8; |
| dev->buf_len--; |
| } |
| } else |
| dev_err(dev->dev, "RRDY IRQ while no data requested\n"); |
| break; |
| case 0x05: /* Transmit data ready */ |
| if (dev->buf_len) { |
| w = *dev->buf++; |
| dev->buf_len--; |
| if (dev->buf_len) { |
| w |= *dev->buf++ << 8; |
| dev->buf_len--; |
| } |
| omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w); |
| } else |
| dev_err(dev->dev, "XRDY IRQ while no data to send\n"); |
| break; |
| default: |
| return IRQ_NONE; |
| } |
| |
| return IRQ_HANDLED; |
| } |
| #else |
| #define omap_i2c_omap1_isr NULL |
| #endif |
| |
| /* |
| * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing |
| * data to DATA_REG. Otherwise some data bytes can be lost while transferring |
| * them from the memory to the I2C interface. |
| */ |
| static int errata_omap3_i462(struct omap_i2c_dev *dev) |
| { |
| unsigned long timeout = 10000; |
| u16 stat; |
| |
| do { |
| stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); |
| if (stat & OMAP_I2C_STAT_XUDF) |
| break; |
| |
| if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { |
| omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY | |
| OMAP_I2C_STAT_XDR)); |
| if (stat & OMAP_I2C_STAT_NACK) { |
| dev->cmd_err |= OMAP_I2C_STAT_NACK; |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK); |
| } |
| |
| if (stat & OMAP_I2C_STAT_AL) { |
| dev_err(dev->dev, "Arbitration lost\n"); |
| dev->cmd_err |= OMAP_I2C_STAT_AL; |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL); |
| } |
| |
| return -EIO; |
| } |
| |
| cpu_relax(); |
| } while (--timeout); |
| |
| if (!timeout) { |
| dev_err(dev->dev, "timeout waiting on XUDF bit\n"); |
| return 0; |
| } |
| |
| return 0; |
| } |
| |
| static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes, |
| bool is_rdr) |
| { |
| u16 w; |
| |
| while (num_bytes--) { |
| w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG); |
| *dev->buf++ = w; |
| dev->buf_len--; |
| |
| /* |
| * Data reg in 2430, omap3 and |
| * omap4 is 8 bit wide |
| */ |
| if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) { |
| *dev->buf++ = w >> 8; |
| dev->buf_len--; |
| } |
| } |
| } |
| |
| static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes, |
| bool is_xdr) |
| { |
| u16 w; |
| |
| while (num_bytes--) { |
| w = *dev->buf++; |
| dev->buf_len--; |
| |
| /* |
| * Data reg in 2430, omap3 and |
| * omap4 is 8 bit wide |
| */ |
| if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) { |
| w |= *dev->buf++ << 8; |
| dev->buf_len--; |
| } |
| |
| if (dev->errata & I2C_OMAP_ERRATA_I462) { |
| int ret; |
| |
| ret = errata_omap3_i462(dev); |
| if (ret < 0) |
| return ret; |
| } |
| |
| omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w); |
| } |
| |
| return 0; |
| } |
| |
| static irqreturn_t |
| omap_i2c_isr(int irq, void *dev_id) |
| { |
| struct omap_i2c_dev *dev = dev_id; |
| irqreturn_t ret = IRQ_HANDLED; |
| u16 mask; |
| u16 stat; |
| |
| spin_lock(&dev->lock); |
| mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); |
| stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); |
| |
| if (stat & mask) |
| ret = IRQ_WAKE_THREAD; |
| |
| spin_unlock(&dev->lock); |
| |
| return ret; |
| } |
| |
| static irqreturn_t |
| omap_i2c_isr_thread(int this_irq, void *dev_id) |
| { |
| struct omap_i2c_dev *dev = dev_id; |
| unsigned long flags; |
| u16 bits; |
| u16 stat; |
| int err = 0, count = 0; |
| |
| spin_lock_irqsave(&dev->lock, flags); |
| do { |
| bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); |
| stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); |
| stat &= bits; |
| |
| /* If we're in receiver mode, ignore XDR/XRDY */ |
| if (dev->receiver) |
| stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY); |
| else |
| stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY); |
| |
| if (!stat) { |
| /* my work here is done */ |
| goto out; |
| } |
| |
| dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat); |
| if (count++ == 100) { |
| dev_warn(dev->dev, "Too much work in one IRQ\n"); |
| break; |
| } |
| |
| if (stat & OMAP_I2C_STAT_NACK) { |
| err |= OMAP_I2C_STAT_NACK; |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK); |
| } |
| |
| if (stat & OMAP_I2C_STAT_AL) { |
| dev_err(dev->dev, "Arbitration lost\n"); |
| err |= OMAP_I2C_STAT_AL; |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL); |
| } |
| |
| /* |
| * ProDB0017052: Clear ARDY bit twice |
| */ |
| if (stat & OMAP_I2C_STAT_ARDY) |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ARDY); |
| |
| if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK | |
| OMAP_I2C_STAT_AL)) { |
| omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY | |
| OMAP_I2C_STAT_RDR | |
| OMAP_I2C_STAT_XRDY | |
| OMAP_I2C_STAT_XDR | |
| OMAP_I2C_STAT_ARDY)); |
| break; |
| } |
| |
| if (stat & OMAP_I2C_STAT_RDR) { |
| u8 num_bytes = 1; |
| |
| if (dev->fifo_size) |
| num_bytes = dev->buf_len; |
| |
| if (dev->errata & I2C_OMAP_ERRATA_I207) { |
| i2c_omap_errata_i207(dev, stat); |
| num_bytes = (omap_i2c_read_reg(dev, |
| OMAP_I2C_BUFSTAT_REG) >> 8) & 0x3F; |
| } |
| |
| omap_i2c_receive_data(dev, num_bytes, true); |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR); |
| continue; |
| } |
| |
| if (stat & OMAP_I2C_STAT_RRDY) { |
| u8 num_bytes = 1; |
| |
| if (dev->threshold) |
| num_bytes = dev->threshold; |
| |
| omap_i2c_receive_data(dev, num_bytes, false); |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY); |
| continue; |
| } |
| |
| if (stat & OMAP_I2C_STAT_XDR) { |
| u8 num_bytes = 1; |
| int ret; |
| |
| if (dev->fifo_size) |
| num_bytes = dev->buf_len; |
| |
| ret = omap_i2c_transmit_data(dev, num_bytes, true); |
| if (ret < 0) |
| break; |
| |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR); |
| continue; |
| } |
| |
| if (stat & OMAP_I2C_STAT_XRDY) { |
| u8 num_bytes = 1; |
| int ret; |
| |
| if (dev->threshold) |
| num_bytes = dev->threshold; |
| |
| ret = omap_i2c_transmit_data(dev, num_bytes, false); |
| if (ret < 0) |
| break; |
| |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY); |
| continue; |
| } |
| |
| if (stat & OMAP_I2C_STAT_ROVR) { |
| dev_err(dev->dev, "Receive overrun\n"); |
| err |= OMAP_I2C_STAT_ROVR; |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR); |
| break; |
| } |
| |
| if (stat & OMAP_I2C_STAT_XUDF) { |
| dev_err(dev->dev, "Transmit underflow\n"); |
| err |= OMAP_I2C_STAT_XUDF; |
| omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF); |
| break; |
| } |
| } while (stat); |
| |
| omap_i2c_complete_cmd(dev, err); |
| |
| out: |
| spin_unlock_irqrestore(&dev->lock, flags); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static const struct i2c_algorithm omap_i2c_algo = { |
| .master_xfer = omap_i2c_xfer, |
| .functionality = omap_i2c_func, |
| }; |
| |
| #ifdef CONFIG_OF |
| static struct omap_i2c_bus_platform_data omap2420_pdata = { |
| .rev = OMAP_I2C_IP_VERSION_1, |
| .flags = OMAP_I2C_FLAG_NO_FIFO | |
| OMAP_I2C_FLAG_SIMPLE_CLOCK | |
| OMAP_I2C_FLAG_16BIT_DATA_REG | |
| OMAP_I2C_FLAG_BUS_SHIFT_2, |
| }; |
| |
| static struct omap_i2c_bus_platform_data omap2430_pdata = { |
| .rev = OMAP_I2C_IP_VERSION_1, |
| .flags = OMAP_I2C_FLAG_BUS_SHIFT_2 | |
| OMAP_I2C_FLAG_FORCE_19200_INT_CLK, |
| }; |
| |
| static struct omap_i2c_bus_platform_data omap3_pdata = { |
| .rev = OMAP_I2C_IP_VERSION_1, |
| .flags = OMAP_I2C_FLAG_BUS_SHIFT_2, |
| }; |
| |
| static struct omap_i2c_bus_platform_data omap4_pdata = { |
| .rev = OMAP_I2C_IP_VERSION_2, |
| }; |
| |
| static const struct of_device_id omap_i2c_of_match[] = { |
| { |
| .compatible = "ti,omap4-i2c", |
| .data = &omap4_pdata, |
| }, |
| { |
| .compatible = "ti,omap3-i2c", |
| .data = &omap3_pdata, |
| }, |
| { |
| .compatible = "ti,omap2430-i2c", |
| .data = &omap2430_pdata, |
| }, |
| { |
| .compatible = "ti,omap2420-i2c", |
| .data = &omap2420_pdata, |
| }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, omap_i2c_of_match); |
| #endif |
| |
| #define OMAP_I2C_SCHEME(rev) ((rev & 0xc000) >> 14) |
| |
| #define OMAP_I2C_REV_SCHEME_0_MAJOR(rev) (rev >> 4) |
| #define OMAP_I2C_REV_SCHEME_0_MINOR(rev) (rev & 0xf) |
| |
| #define OMAP_I2C_REV_SCHEME_1_MAJOR(rev) ((rev & 0x0700) >> 7) |
| #define OMAP_I2C_REV_SCHEME_1_MINOR(rev) (rev & 0x1f) |
| #define OMAP_I2C_SCHEME_0 0 |
| #define OMAP_I2C_SCHEME_1 1 |
| |
| static int omap_i2c_get_scl(struct i2c_adapter *adap) |
| { |
| struct omap_i2c_dev *dev = i2c_get_adapdata(adap); |
| u32 reg; |
| |
| reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); |
| |
| return reg & OMAP_I2C_SYSTEST_SCL_I_FUNC; |
| } |
| |
| static int omap_i2c_get_sda(struct i2c_adapter *adap) |
| { |
| struct omap_i2c_dev *dev = i2c_get_adapdata(adap); |
| u32 reg; |
| |
| reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); |
| |
| return reg & OMAP_I2C_SYSTEST_SDA_I_FUNC; |
| } |
| |
| static void omap_i2c_set_scl(struct i2c_adapter *adap, int val) |
| { |
| struct omap_i2c_dev *dev = i2c_get_adapdata(adap); |
| u32 reg; |
| |
| reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); |
| if (val) |
| reg |= OMAP_I2C_SYSTEST_SCL_O; |
| else |
| reg &= ~OMAP_I2C_SYSTEST_SCL_O; |
| omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); |
| } |
| |
| static void omap_i2c_prepare_recovery(struct i2c_adapter *adap) |
| { |
| struct omap_i2c_dev *dev = i2c_get_adapdata(adap); |
| u32 reg; |
| |
| reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); |
| /* enable test mode */ |
| reg |= OMAP_I2C_SYSTEST_ST_EN; |
| /* select SDA/SCL IO mode */ |
| reg |= 3 << OMAP_I2C_SYSTEST_TMODE_SHIFT; |
| /* set SCL to high-impedance state (reset value is 0) */ |
| reg |= OMAP_I2C_SYSTEST_SCL_O; |
| /* set SDA to high-impedance state (reset value is 0) */ |
| reg |= OMAP_I2C_SYSTEST_SDA_O; |
| omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); |
| } |
| |
| static void omap_i2c_unprepare_recovery(struct i2c_adapter *adap) |
| { |
| struct omap_i2c_dev *dev = i2c_get_adapdata(adap); |
| u32 reg; |
| |
| reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); |
| /* restore reset values */ |
| reg &= ~OMAP_I2C_SYSTEST_ST_EN; |
| reg &= ~OMAP_I2C_SYSTEST_TMODE_MASK; |
| reg &= ~OMAP_I2C_SYSTEST_SCL_O; |
| reg &= ~OMAP_I2C_SYSTEST_SDA_O; |
| omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); |
| } |
| |
| static struct i2c_bus_recovery_info omap_i2c_bus_recovery_info = { |
| .get_scl = omap_i2c_get_scl, |
| .get_sda = omap_i2c_get_sda, |
| .set_scl = omap_i2c_set_scl, |
| .prepare_recovery = omap_i2c_prepare_recovery, |
| .unprepare_recovery = omap_i2c_unprepare_recovery, |
| .recover_bus = i2c_generic_scl_recovery, |
| }; |
| |
| static int |
| omap_i2c_probe(struct platform_device *pdev) |
| { |
| struct omap_i2c_dev *dev; |
| struct i2c_adapter *adap; |
| struct resource *mem; |
| const struct omap_i2c_bus_platform_data *pdata = |
| dev_get_platdata(&pdev->dev); |
| struct device_node *node = pdev->dev.of_node; |
| const struct of_device_id *match; |
| int irq; |
| int r; |
| u32 rev; |
| u16 minor, major; |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq < 0) { |
| dev_err(&pdev->dev, "no irq resource?\n"); |
| return irq; |
| } |
| |
| dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL); |
| if (!dev) |
| return -ENOMEM; |
| |
| mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| dev->base = devm_ioremap_resource(&pdev->dev, mem); |
| if (IS_ERR(dev->base)) |
| return PTR_ERR(dev->base); |
| |
| match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev); |
| if (match) { |
| u32 freq = 100000; /* default to 100000 Hz */ |
| |
| pdata = match->data; |
| dev->flags = pdata->flags; |
| |
| of_property_read_u32(node, "clock-frequency", &freq); |
| /* convert DT freq value in Hz into kHz for speed */ |
| dev->speed = freq / 1000; |
| } else if (pdata != NULL) { |
| dev->speed = pdata->clkrate; |
| dev->flags = pdata->flags; |
| dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat; |
| } |
| |
| dev->dev = &pdev->dev; |
| dev->irq = irq; |
| |
| spin_lock_init(&dev->lock); |
| |
| platform_set_drvdata(pdev, dev); |
| init_completion(&dev->cmd_complete); |
| |
| dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3; |
| |
| pm_runtime_enable(dev->dev); |
| pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT); |
| pm_runtime_use_autosuspend(dev->dev); |
| |
| r = pm_runtime_get_sync(dev->dev); |
| if (r < 0) |
| goto err_free_mem; |
| |
| /* |
| * Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2. |
| * On omap1/3/2 Offset 4 is IE Reg the bit [15:14] is 0 at reset. |
| * Also since the omap_i2c_read_reg uses reg_map_ip_* a |
| * readw_relaxed is done. |
| */ |
| rev = readw_relaxed(dev->base + 0x04); |
| |
| dev->scheme = OMAP_I2C_SCHEME(rev); |
| switch (dev->scheme) { |
| case OMAP_I2C_SCHEME_0: |
| dev->regs = (u8 *)reg_map_ip_v1; |
| dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG); |
| minor = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev); |
| major = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev); |
| break; |
| case OMAP_I2C_SCHEME_1: |
| /* FALLTHROUGH */ |
| default: |
| dev->regs = (u8 *)reg_map_ip_v2; |
| rev = (rev << 16) | |
| omap_i2c_read_reg(dev, OMAP_I2C_IP_V2_REVNB_LO); |
| minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev); |
| major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev); |
| dev->rev = rev; |
| } |
| |
| dev->errata = 0; |
| |
| if (dev->rev >= OMAP_I2C_REV_ON_2430 && |
| dev->rev < OMAP_I2C_REV_ON_4430_PLUS) |
| dev->errata |= I2C_OMAP_ERRATA_I207; |
| |
| if (dev->rev <= OMAP_I2C_REV_ON_3430_3530) |
| dev->errata |= I2C_OMAP_ERRATA_I462; |
| |
| if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) { |
| u16 s; |
| |
| /* Set up the fifo size - Get total size */ |
| s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3; |
| dev->fifo_size = 0x8 << s; |
| |
| /* |
| * Set up notification threshold as half the total available |
| * size. This is to ensure that we can handle the status on int |
| * call back latencies. |
| */ |
| |
| dev->fifo_size = (dev->fifo_size / 2); |
| |
| if (dev->rev < OMAP_I2C_REV_ON_3630) |
| dev->b_hw = 1; /* Enable hardware fixes */ |
| |
| /* calculate wakeup latency constraint for MPU */ |
| if (dev->set_mpu_wkup_lat != NULL) |
| dev->latency = (1000000 * dev->fifo_size) / |
| (1000 * dev->speed / 8); |
| } |
| |
| /* reset ASAP, clearing any IRQs */ |
| omap_i2c_init(dev); |
| |
| if (dev->rev < OMAP_I2C_OMAP1_REV_2) |
| r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr, |
| IRQF_NO_SUSPEND, pdev->name, dev); |
| else |
| r = devm_request_threaded_irq(&pdev->dev, dev->irq, |
| omap_i2c_isr, omap_i2c_isr_thread, |
| IRQF_NO_SUSPEND | IRQF_ONESHOT, |
| pdev->name, dev); |
| |
| if (r) { |
| dev_err(dev->dev, "failure requesting irq %i\n", dev->irq); |
| goto err_unuse_clocks; |
| } |
| |
| adap = &dev->adapter; |
| i2c_set_adapdata(adap, dev); |
| adap->owner = THIS_MODULE; |
| adap->class = I2C_CLASS_DEPRECATED; |
| 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; |
| adap->bus_recovery_info = &omap_i2c_bus_recovery_info; |
| |
| /* i2c device drivers may be active on return from add_adapter() */ |
| adap->nr = pdev->id; |
| r = i2c_add_numbered_adapter(adap); |
| if (r) { |
| dev_err(dev->dev, "failure adding adapter\n"); |
| goto err_unuse_clocks; |
| } |
| |
| dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr, |
| major, minor, dev->speed); |
| |
| pm_runtime_mark_last_busy(dev->dev); |
| pm_runtime_put_autosuspend(dev->dev); |
| |
| return 0; |
| |
| err_unuse_clocks: |
| omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); |
| pm_runtime_put(dev->dev); |
| pm_runtime_disable(&pdev->dev); |
| err_free_mem: |
| |
| return r; |
| } |
| |
| static int omap_i2c_remove(struct platform_device *pdev) |
| { |
| struct omap_i2c_dev *dev = platform_get_drvdata(pdev); |
| int ret; |
| |
| 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); |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| static int omap_i2c_runtime_suspend(struct device *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct omap_i2c_dev *_dev = platform_get_drvdata(pdev); |
| |
| _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG); |
| |
| if (_dev->scheme == OMAP_I2C_SCHEME_0) |
| omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0); |
| else |
| omap_i2c_write_reg(_dev, OMAP_I2C_IP_V2_IRQENABLE_CLR, |
| OMAP_I2C_IP_V2_INTERRUPTS_MASK); |
| |
| if (_dev->rev < OMAP_I2C_OMAP1_REV_2) { |
| omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */ |
| } else { |
| omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate); |
| |
| /* Flush posted write */ |
| omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG); |
| } |
| |
| pinctrl_pm_select_sleep_state(dev); |
| |
| 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); |
| |
| pinctrl_pm_select_default_state(dev); |
| |
| if (!_dev->regs) |
| return 0; |
| |
| __omap_i2c_init(_dev); |
| |
| return 0; |
| } |
| |
| static struct dev_pm_ops omap_i2c_pm_ops = { |
| SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend, |
| omap_i2c_runtime_resume, NULL) |
| }; |
| #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops) |
| #else |
| #define OMAP_I2C_PM_OPS NULL |
| #endif /* CONFIG_PM */ |
| |
| static struct platform_driver omap_i2c_driver = { |
| .probe = omap_i2c_probe, |
| .remove = omap_i2c_remove, |
| .driver = { |
| .name = "omap_i2c", |
| .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"); |