forked from mirrors/linux
		
	i2c: brcmstb: Add Broadcom settop SoC i2c controller driver
Adding support for i2c controller driver for Broadcom settop SoCs. Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> [wsa: removed superfluous owner in platform_driver] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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								Documentation/devicetree/bindings/i2c/i2c-brcmstb.txt
									
									
									
									
									
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								Documentation/devicetree/bindings/i2c/i2c-brcmstb.txt
									
									
									
									
									
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							|  | @ -0,0 +1,28 @@ | |||
| Broadcom stb bsc iic master controller | ||||
| 
 | ||||
| Required properties: | ||||
| 
 | ||||
| - compatible: should be "brcm,brcmstb-i2c" | ||||
| - clock-frequency: 32-bit decimal value of iic master clock freqency in Hz | ||||
| 		   valid values are 375000, 390000, 187500, 200000 | ||||
| 		   93750, 97500, 46875 and 50000 | ||||
| - reg: specifies the base physical address and size of the registers | ||||
| 
 | ||||
| Optional properties : | ||||
| 
 | ||||
| - interrupt-parent: specifies the phandle to the parent interrupt controller | ||||
|   this one is cascaded from | ||||
| - interrupts: specifies the interrupt number, the irq line to be used | ||||
| - interrupt-names: Interrupt name string | ||||
| 
 | ||||
| Example: | ||||
| 
 | ||||
| bsca: i2c@f0406200 { | ||||
|       clock-frequency = <390000>; | ||||
|       compatible = "brcm,brcmstb-i2c"; | ||||
|       interrupt-parent = <&irq0_intc>; | ||||
|       reg = <0xf0406200 0x58>; | ||||
|       interrupts = <0x18>; | ||||
|       interrupt-names = "upg_bsca"; | ||||
| }; | ||||
| 
 | ||||
|  | @ -392,6 +392,16 @@ config I2C_BCM_KONA | |||
| 
 | ||||
| 	  If you do not need KONA I2C interface, say N. | ||||
| 
 | ||||
| config I2C_BRCMSTB | ||||
| 	tristate "BRCM Settop I2C controller" | ||||
| 	depends on ARCH_BRCMSTB || COMPILE_TEST | ||||
| 	default y | ||||
| 	help | ||||
| 	  If you say yes to this option, support will be included for the | ||||
| 	  I2C interface on the Broadcom Settop SoCs. | ||||
| 
 | ||||
| 	  If you do not need I2C interface, say N. | ||||
| 
 | ||||
| config I2C_BLACKFIN_TWI | ||||
| 	tristate "Blackfin TWI I2C support" | ||||
| 	depends on BLACKFIN | ||||
|  |  | |||
|  | @ -106,6 +106,7 @@ obj-$(CONFIG_I2C_VIPERBOARD)	+= i2c-viperboard.o | |||
| # Other I2C/SMBus bus drivers
 | ||||
| obj-$(CONFIG_I2C_ACORN)		+= i2c-acorn.o | ||||
| obj-$(CONFIG_I2C_BCM_KONA)	+= i2c-bcm-kona.o | ||||
| obj-$(CONFIG_I2C_BRCMSTB)	+= i2c-brcmstb.o | ||||
| obj-$(CONFIG_I2C_CROS_EC_TUNNEL)	+= i2c-cros-ec-tunnel.o | ||||
| obj-$(CONFIG_I2C_ELEKTOR)	+= i2c-elektor.o | ||||
| obj-$(CONFIG_I2C_OPAL)		+= i2c-opal.o | ||||
|  |  | |||
							
								
								
									
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								drivers/i2c/busses/i2c-brcmstb.c
									
									
									
									
									
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								drivers/i2c/busses/i2c-brcmstb.c
									
									
									
									
									
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							|  | @ -0,0 +1,694 @@ | |||
| /*
 | ||||
|  * Copyright (C) 2014 Broadcom Corporation | ||||
|  * | ||||
|  * 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 version 2. | ||||
|  * | ||||
|  * This program is distributed "as is" WITHOUT ANY WARRANTY of any | ||||
|  * kind, whether express or implied; without even the implied warranty | ||||
|  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | ||||
|  * GNU General Public License for more details. | ||||
|  */ | ||||
| 
 | ||||
| #include <linux/clk.h> | ||||
| #include <linux/delay.h> | ||||
| #include <linux/device.h> | ||||
| #include <linux/i2c.h> | ||||
| #include <linux/interrupt.h> | ||||
| #include <linux/io.h> | ||||
| #include <linux/kernel.h> | ||||
| #include <linux/module.h> | ||||
| #include <linux/platform_device.h> | ||||
| #include <linux/sched.h> | ||||
| #include <linux/slab.h> | ||||
| #include <linux/version.h> | ||||
| 
 | ||||
| #define N_DATA_REGS					8 | ||||
| #define N_DATA_BYTES					(N_DATA_REGS * 4) | ||||
| 
 | ||||
| /* BSC count register field definitions */ | ||||
| #define BSC_CNT_REG1_MASK				0x0000003f | ||||
| #define BSC_CNT_REG1_SHIFT				0 | ||||
| #define BSC_CNT_REG2_MASK				0x00000fc0 | ||||
| #define BSC_CNT_REG2_SHIFT				6 | ||||
| 
 | ||||
| /* BSC CTL register field definitions */ | ||||
| #define BSC_CTL_REG_DTF_MASK				0x00000003 | ||||
| #define BSC_CTL_REG_SCL_SEL_MASK			0x00000030 | ||||
| #define BSC_CTL_REG_SCL_SEL_SHIFT			4 | ||||
| #define BSC_CTL_REG_INT_EN_MASK				0x00000040 | ||||
| #define BSC_CTL_REG_INT_EN_SHIFT			6 | ||||
| #define BSC_CTL_REG_DIV_CLK_MASK			0x00000080 | ||||
| 
 | ||||
| /* BSC_IIC_ENABLE r/w enable and interrupt field defintions */ | ||||
| #define BSC_IIC_EN_RESTART_MASK				0x00000040 | ||||
| #define BSC_IIC_EN_NOSTART_MASK				0x00000020 | ||||
| #define BSC_IIC_EN_NOSTOP_MASK				0x00000010 | ||||
| #define BSC_IIC_EN_NOACK_MASK				0x00000004 | ||||
| #define BSC_IIC_EN_INTRP_MASK				0x00000002 | ||||
| #define BSC_IIC_EN_ENABLE_MASK				0x00000001 | ||||
| 
 | ||||
| /* BSC_CTLHI control register field definitions */ | ||||
| #define BSC_CTLHI_REG_INPUT_SWITCHING_LEVEL_MASK	0x00000080 | ||||
| #define BSC_CTLHI_REG_DATAREG_SIZE_MASK			0x00000040 | ||||
| #define BSC_CTLHI_REG_IGNORE_ACK_MASK			0x00000002 | ||||
| #define BSC_CTLHI_REG_WAIT_DIS_MASK			0x00000001 | ||||
| 
 | ||||
| #define I2C_TIMEOUT					100 /* msecs */ | ||||
| 
 | ||||
| /* Condition mask used for non combined transfer */ | ||||
| #define COND_RESTART		BSC_IIC_EN_RESTART_MASK | ||||
| #define COND_NOSTART		BSC_IIC_EN_NOSTART_MASK | ||||
| #define COND_NOSTOP		BSC_IIC_EN_NOSTOP_MASK | ||||
| #define COND_START_STOP		(COND_RESTART | COND_NOSTART | COND_NOSTOP) | ||||
| 
 | ||||
| /* BSC data transfer direction */ | ||||
| #define DTF_WR_MASK		0x00000000 | ||||
| #define DTF_RD_MASK		0x00000001 | ||||
| /* BSC data transfer direction combined format */ | ||||
| #define DTF_RD_WR_MASK		0x00000002 | ||||
| #define DTF_WR_RD_MASK		0x00000003 | ||||
| 
 | ||||
| #define INT_ENABLE		true | ||||
| #define INT_DISABLE		false | ||||
| 
 | ||||
| /* BSC block register map structure to cache fields to be written */ | ||||
| struct bsc_regs { | ||||
| 	u32	chip_address;           /* slave address */ | ||||
| 	u32	data_in[N_DATA_REGS];   /* tx data buffer*/ | ||||
| 	u32	cnt_reg;		/* rx/tx data length */ | ||||
| 	u32	ctl_reg;		/* control register */ | ||||
| 	u32	iic_enable;		/* xfer enable and status */ | ||||
| 	u32	data_out[N_DATA_REGS];  /* rx data buffer */ | ||||
| 	u32	ctlhi_reg;		/* more control fields */ | ||||
| 	u32	scl_param;		/* reserved */ | ||||
| }; | ||||
| 
 | ||||
| struct bsc_clk_param { | ||||
| 	u32 hz; | ||||
| 	u32 scl_mask; | ||||
| 	u32 div_mask; | ||||
| }; | ||||
| 
 | ||||
| enum bsc_xfer_cmd { | ||||
| 	CMD_WR, | ||||
| 	CMD_RD, | ||||
| 	CMD_WR_NOACK, | ||||
| 	CMD_RD_NOACK, | ||||
| }; | ||||
| 
 | ||||
| static char const *cmd_string[] = { | ||||
| 	[CMD_WR] = "WR", | ||||
| 	[CMD_RD] = "RD", | ||||
| 	[CMD_WR_NOACK] = "WR NOACK", | ||||
| 	[CMD_RD_NOACK] = "RD NOACK", | ||||
| }; | ||||
| 
 | ||||
| enum bus_speeds { | ||||
| 	SPD_375K, | ||||
| 	SPD_390K, | ||||
| 	SPD_187K, | ||||
| 	SPD_200K, | ||||
| 	SPD_93K, | ||||
| 	SPD_97K, | ||||
| 	SPD_46K, | ||||
| 	SPD_50K | ||||
| }; | ||||
| 
 | ||||
| static const struct bsc_clk_param bsc_clk[] = { | ||||
| 	[SPD_375K] = { | ||||
| 		.hz = 375000, | ||||
| 		.scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT, | ||||
| 		.div_mask = 0 | ||||
| 	}, | ||||
| 	[SPD_390K] = { | ||||
| 		.hz = 390000, | ||||
| 		.scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT, | ||||
| 		.div_mask = 0 | ||||
| 	}, | ||||
| 	[SPD_187K] = { | ||||
| 		.hz = 187500, | ||||
| 		.scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT, | ||||
| 		.div_mask = 0 | ||||
| 	}, | ||||
| 	[SPD_200K] = { | ||||
| 		.hz = 200000, | ||||
| 		.scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT, | ||||
| 		.div_mask = 0 | ||||
| 	}, | ||||
| 	[SPD_93K]  = { | ||||
| 		.hz = 93750, | ||||
| 		.scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT, | ||||
| 		.div_mask = BSC_CTL_REG_DIV_CLK_MASK | ||||
| 	}, | ||||
| 	[SPD_97K]  = { | ||||
| 		.hz = 97500, | ||||
| 		.scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT, | ||||
| 		.div_mask = BSC_CTL_REG_DIV_CLK_MASK | ||||
| 	}, | ||||
| 	[SPD_46K]  = { | ||||
| 		.hz = 46875, | ||||
| 		.scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT, | ||||
| 		.div_mask = BSC_CTL_REG_DIV_CLK_MASK | ||||
| 	}, | ||||
| 	[SPD_50K]  = { | ||||
| 		.hz = 50000, | ||||
| 		.scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT, | ||||
| 		.div_mask = BSC_CTL_REG_DIV_CLK_MASK | ||||
| 	} | ||||
| }; | ||||
| 
 | ||||
| struct brcmstb_i2c_dev { | ||||
| 	struct device *device; | ||||
| 	void __iomem *base; | ||||
| 	void __iomem *irq_base; | ||||
| 	int irq; | ||||
| 	struct bsc_regs *bsc_regmap; | ||||
| 	struct i2c_adapter adapter; | ||||
| 	struct completion done; | ||||
| 	bool is_suspended; | ||||
| 	u32 clk_freq_hz; | ||||
| }; | ||||
| 
 | ||||
| /* register accessors for both be and le cpu arch */ | ||||
| #ifdef CONFIG_CPU_BIG_ENDIAN | ||||
| #define __bsc_readl(_reg) ioread32be(_reg) | ||||
| #define __bsc_writel(_val, _reg) iowrite32be(_val, _reg) | ||||
| #else | ||||
| #define __bsc_readl(_reg) ioread32(_reg) | ||||
| #define __bsc_writel(_val, _reg) iowrite32(_val, _reg) | ||||
| #endif | ||||
| 
 | ||||
| #define bsc_readl(_dev, _reg)						\ | ||||
| 	__bsc_readl(_dev->base + offsetof(struct bsc_regs, _reg)) | ||||
| 
 | ||||
| #define bsc_writel(_dev, _val, _reg)					\ | ||||
| 	__bsc_writel(_val, _dev->base + offsetof(struct bsc_regs, _reg)) | ||||
| 
 | ||||
| static void brcmstb_i2c_enable_disable_irq(struct brcmstb_i2c_dev *dev, | ||||
| 					   bool int_en) | ||||
| { | ||||
| 
 | ||||
| 	if (int_en) | ||||
| 		/* Enable BSC  CTL interrupt line */ | ||||
| 		dev->bsc_regmap->ctl_reg |= BSC_CTL_REG_INT_EN_MASK; | ||||
| 	else | ||||
| 		/* Disable BSC CTL interrupt line */ | ||||
| 		dev->bsc_regmap->ctl_reg &= ~BSC_CTL_REG_INT_EN_MASK; | ||||
| 
 | ||||
| 	barrier(); | ||||
| 	bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg); | ||||
| } | ||||
| 
 | ||||
| static irqreturn_t brcmstb_i2c_isr(int irq, void *devid) | ||||
| { | ||||
| 	struct brcmstb_i2c_dev *dev = devid; | ||||
| 	u32 status_bsc_ctl = bsc_readl(dev, ctl_reg); | ||||
| 	u32 status_iic_intrp = bsc_readl(dev, iic_enable); | ||||
| 
 | ||||
| 	dev_dbg(dev->device, "isr CTL_REG %x IIC_EN %x\n", | ||||
| 		status_bsc_ctl, status_iic_intrp); | ||||
| 
 | ||||
| 	if (!(status_bsc_ctl & BSC_CTL_REG_INT_EN_MASK)) | ||||
| 		return IRQ_NONE; | ||||
| 
 | ||||
| 	brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE); | ||||
| 	complete_all(&dev->done); | ||||
| 
 | ||||
| 	dev_dbg(dev->device, "isr handled"); | ||||
| 	return IRQ_HANDLED; | ||||
| } | ||||
| 
 | ||||
| /* Wait for device to be ready */ | ||||
| static int brcmstb_i2c_wait_if_busy(struct brcmstb_i2c_dev *dev) | ||||
| { | ||||
| 	unsigned long timeout = jiffies + msecs_to_jiffies(I2C_TIMEOUT); | ||||
| 
 | ||||
| 	while ((bsc_readl(dev, iic_enable) & BSC_IIC_EN_INTRP_MASK)) { | ||||
| 		if (time_after(jiffies, timeout)) | ||||
| 			return -ETIMEDOUT; | ||||
| 		cpu_relax(); | ||||
| 	} | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| /* i2c xfer completion function, handles both irq and polling mode */ | ||||
| static int brcmstb_i2c_wait_for_completion(struct brcmstb_i2c_dev *dev) | ||||
| { | ||||
| 	int ret = 0; | ||||
| 	unsigned long timeout = msecs_to_jiffies(I2C_TIMEOUT); | ||||
| 
 | ||||
| 	if (dev->irq >= 0) { | ||||
| 		if (!wait_for_completion_timeout(&dev->done, timeout)) | ||||
| 			ret = -ETIMEDOUT; | ||||
| 	} else { | ||||
| 		/* we are in polling mode */ | ||||
| 		u32 bsc_intrp; | ||||
| 		unsigned long time_left = jiffies + timeout; | ||||
| 
 | ||||
| 		do { | ||||
| 			bsc_intrp = bsc_readl(dev, iic_enable) & | ||||
| 				BSC_IIC_EN_INTRP_MASK; | ||||
| 			if (time_after(jiffies, time_left)) { | ||||
| 				ret = -ETIMEDOUT; | ||||
| 				break; | ||||
| 			} | ||||
| 			cpu_relax(); | ||||
| 		} while (!bsc_intrp); | ||||
| 	} | ||||
| 
 | ||||
| 	if (dev->irq < 0 || ret == -ETIMEDOUT) | ||||
| 		brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE); | ||||
| 
 | ||||
| 	return ret; | ||||
| } | ||||
| 
 | ||||
| /* Set xfer START/STOP conditions for subsequent transfer */ | ||||
| static void brcmstb_set_i2c_start_stop(struct brcmstb_i2c_dev *dev, | ||||
| 				       u32 cond_flag) | ||||
| { | ||||
| 	u32 regval = dev->bsc_regmap->iic_enable; | ||||
| 
 | ||||
| 	dev->bsc_regmap->iic_enable = (regval & ~COND_START_STOP) | cond_flag; | ||||
| } | ||||
| 
 | ||||
| /* Send I2C request check completion */ | ||||
| static int brcmstb_send_i2c_cmd(struct brcmstb_i2c_dev *dev, | ||||
| 				enum bsc_xfer_cmd cmd) | ||||
| { | ||||
| 	int rc = 0; | ||||
| 	struct bsc_regs *pi2creg = dev->bsc_regmap; | ||||
| 
 | ||||
| 	/* Make sure the hardware is ready */ | ||||
| 	rc = brcmstb_i2c_wait_if_busy(dev); | ||||
| 	if (rc < 0) | ||||
| 		return rc; | ||||
| 
 | ||||
| 	/* only if we are in interrupt mode */ | ||||
| 	if (dev->irq >= 0) | ||||
| 		reinit_completion(&dev->done); | ||||
| 
 | ||||
| 	/* enable BSC CTL interrupt line */ | ||||
| 	brcmstb_i2c_enable_disable_irq(dev, INT_ENABLE); | ||||
| 
 | ||||
| 	/* initiate transfer by setting iic_enable */ | ||||
| 	pi2creg->iic_enable |= BSC_IIC_EN_ENABLE_MASK; | ||||
| 	bsc_writel(dev, pi2creg->iic_enable, iic_enable); | ||||
| 
 | ||||
| 	/* Wait for transaction to finish or timeout */ | ||||
| 	rc = brcmstb_i2c_wait_for_completion(dev); | ||||
| 	if (rc) { | ||||
| 		dev_dbg(dev->device, "intr timeout for cmd %s\n", | ||||
| 			cmd_string[cmd]); | ||||
| 		goto cmd_out; | ||||
| 	} | ||||
| 
 | ||||
| 	if ((CMD_RD || CMD_WR) && | ||||
| 	    bsc_readl(dev, iic_enable) & BSC_IIC_EN_NOACK_MASK) { | ||||
| 		rc = -EREMOTEIO; | ||||
| 		dev_dbg(dev->device, "controller received NOACK intr for %s\n", | ||||
| 			cmd_string[cmd]); | ||||
| 	} | ||||
| 
 | ||||
| cmd_out: | ||||
| 	bsc_writel(dev, 0, cnt_reg); | ||||
| 	bsc_writel(dev, 0, iic_enable); | ||||
| 
 | ||||
| 	return rc; | ||||
| } | ||||
| 
 | ||||
| /* Actual data transfer through the BSC master */ | ||||
| static int brcmstb_i2c_xfer_bsc_data(struct brcmstb_i2c_dev *dev, | ||||
| 				     u8 *buf, unsigned int len, | ||||
| 				     struct i2c_msg *pmsg) | ||||
| { | ||||
| 	int cnt, byte, rc; | ||||
| 	enum bsc_xfer_cmd cmd; | ||||
| 	u32 ctl_reg; | ||||
| 	struct bsc_regs *pi2creg = dev->bsc_regmap; | ||||
| 	int no_ack = pmsg->flags & I2C_M_IGNORE_NAK; | ||||
| 
 | ||||
| 	/* see if the transaction needs to check NACK conditions */ | ||||
| 	if (no_ack || len <= N_DATA_BYTES) { | ||||
| 		cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD_NOACK | ||||
| 			: CMD_WR_NOACK; | ||||
| 		pi2creg->ctlhi_reg |= BSC_CTLHI_REG_IGNORE_ACK_MASK; | ||||
| 	} else { | ||||
| 		cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD : CMD_WR; | ||||
| 		pi2creg->ctlhi_reg &= ~BSC_CTLHI_REG_IGNORE_ACK_MASK; | ||||
| 	} | ||||
| 	bsc_writel(dev, pi2creg->ctlhi_reg, ctlhi_reg); | ||||
| 
 | ||||
| 	/* set data transfer direction */ | ||||
| 	ctl_reg = pi2creg->ctl_reg & ~BSC_CTL_REG_DTF_MASK; | ||||
| 	if (cmd == CMD_WR || cmd == CMD_WR_NOACK) | ||||
| 		pi2creg->ctl_reg = ctl_reg | DTF_WR_MASK; | ||||
| 	else | ||||
| 		pi2creg->ctl_reg = ctl_reg | DTF_RD_MASK; | ||||
| 
 | ||||
| 	/* set the read/write length */ | ||||
| 	bsc_writel(dev, BSC_CNT_REG1_MASK & (len << BSC_CNT_REG1_SHIFT), | ||||
| 		   cnt_reg); | ||||
| 
 | ||||
| 	/* Write data into data_in register */ | ||||
| 	if (cmd == CMD_WR || cmd == CMD_WR_NOACK) { | ||||
| 		for (cnt = 0; cnt < len; cnt += 4) { | ||||
| 			u32 word = 0; | ||||
| 
 | ||||
| 			for (byte = 0; byte < 4; byte++) { | ||||
| 				word >>= 8; | ||||
| 				if ((cnt + byte) < len) | ||||
| 					word |= buf[cnt + byte] << 24; | ||||
| 			} | ||||
| 			bsc_writel(dev, word, data_in[cnt >> 2]); | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	/* Initiate xfer, the function will return on completion */ | ||||
| 	rc = brcmstb_send_i2c_cmd(dev, cmd); | ||||
| 
 | ||||
| 	if (rc != 0) { | ||||
| 		dev_dbg(dev->device, "%s failure", cmd_string[cmd]); | ||||
| 		return rc; | ||||
| 	} | ||||
| 
 | ||||
| 	if (cmd == CMD_RD || cmd == CMD_RD_NOACK) { | ||||
| 		for (cnt = 0; cnt < len; cnt += 4) { | ||||
| 			u32 data = bsc_readl(dev, data_out[cnt >> 2]); | ||||
| 
 | ||||
| 			for (byte = 0; byte < 4 && | ||||
| 				     (byte + cnt) < len; byte++) { | ||||
| 				buf[cnt + byte] = data & 0xff; | ||||
| 				data >>= 8; | ||||
| 			} | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| /* Write a single byte of data to the i2c bus */ | ||||
| static int brcmstb_i2c_write_data_byte(struct brcmstb_i2c_dev *dev, | ||||
| 				       u8 *buf, unsigned int nak_expected) | ||||
| { | ||||
| 	enum bsc_xfer_cmd cmd = nak_expected ? CMD_WR : CMD_WR_NOACK; | ||||
| 
 | ||||
| 	bsc_writel(dev, 1, cnt_reg); | ||||
| 	bsc_writel(dev, *buf, data_in); | ||||
| 
 | ||||
| 	return brcmstb_send_i2c_cmd(dev, cmd); | ||||
| } | ||||
| 
 | ||||
| /* Send i2c address */ | ||||
| static int brcmstb_i2c_do_addr(struct brcmstb_i2c_dev *dev, | ||||
| 			       struct i2c_msg *msg) | ||||
| { | ||||
| 	unsigned char addr; | ||||
| 
 | ||||
| 	if (msg->flags & I2C_M_TEN) { | ||||
| 		/* First byte is 11110XX0 where XX is upper 2 bits */ | ||||
| 		addr = 0xF0 | ((msg->addr & 0x300) >> 7); | ||||
| 		bsc_writel(dev, addr, chip_address); | ||||
| 
 | ||||
| 		/* Second byte is the remaining 8 bits */ | ||||
| 		addr = msg->addr & 0xFF; | ||||
| 		if (brcmstb_i2c_write_data_byte(dev, &addr, 0) < 0) | ||||
| 			return -EREMOTEIO; | ||||
| 
 | ||||
| 		if (msg->flags & I2C_M_RD) { | ||||
| 			/* For read, send restart without stop condition */ | ||||
| 			brcmstb_set_i2c_start_stop(dev, COND_RESTART | ||||
| 						   | COND_NOSTOP); | ||||
| 			/* Then re-send the first byte with the read bit set */ | ||||
| 			addr = 0xF0 | ((msg->addr & 0x300) >> 7) | 0x01; | ||||
| 			if (brcmstb_i2c_write_data_byte(dev, &addr, 0) < 0) | ||||
| 				return -EREMOTEIO; | ||||
| 
 | ||||
| 		} | ||||
| 	} else { | ||||
| 		addr = msg->addr << 1; | ||||
| 		if (msg->flags & I2C_M_RD) | ||||
| 			addr |= 1; | ||||
| 
 | ||||
| 		bsc_writel(dev, addr, chip_address); | ||||
| 	} | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| /* Master transfer function */ | ||||
| static int brcmstb_i2c_xfer(struct i2c_adapter *adapter, | ||||
| 			    struct i2c_msg msgs[], int num) | ||||
| { | ||||
| 	struct brcmstb_i2c_dev *dev = i2c_get_adapdata(adapter); | ||||
| 	struct i2c_msg *pmsg; | ||||
| 	int rc = 0; | ||||
| 	int i; | ||||
| 	int bytes_to_xfer; | ||||
| 	u8 *tmp_buf; | ||||
| 	int len = 0; | ||||
| 
 | ||||
| 	if (dev->is_suspended) | ||||
| 		return -EBUSY; | ||||
| 
 | ||||
| 	/* Loop through all messages */ | ||||
| 	for (i = 0; i < num; i++) { | ||||
| 		pmsg = &msgs[i]; | ||||
| 		len = pmsg->len; | ||||
| 		tmp_buf = pmsg->buf; | ||||
| 
 | ||||
| 		dev_dbg(dev->device, | ||||
| 			"msg# %d/%d flg %x buf %x len %d\n", i, | ||||
| 			num - 1, pmsg->flags, | ||||
| 			pmsg->buf ? pmsg->buf[0] : '0', pmsg->len); | ||||
| 
 | ||||
| 		if (i < (num - 1) && (msgs[i + 1].flags & I2C_M_NOSTART)) | ||||
| 			brcmstb_set_i2c_start_stop(dev, ~(COND_START_STOP)); | ||||
| 		else | ||||
| 			brcmstb_set_i2c_start_stop(dev, | ||||
| 						   COND_RESTART | COND_NOSTOP); | ||||
| 
 | ||||
| 		/* Send slave address */ | ||||
| 		if (!(pmsg->flags & I2C_M_NOSTART)) { | ||||
| 			rc = brcmstb_i2c_do_addr(dev, pmsg); | ||||
| 			if (rc < 0) { | ||||
| 				dev_dbg(dev->device, | ||||
| 					"NACK for addr %2.2x msg#%d rc = %d\n", | ||||
| 					pmsg->addr, i, rc); | ||||
| 				goto out; | ||||
| 			} | ||||
| 		} | ||||
| 
 | ||||
| 		/* Perform data transfer */ | ||||
| 		while (len) { | ||||
| 			bytes_to_xfer = min(len, N_DATA_BYTES); | ||||
| 
 | ||||
| 			if (len <= N_DATA_BYTES && i == (num - 1)) | ||||
| 				brcmstb_set_i2c_start_stop(dev, | ||||
| 							   ~(COND_START_STOP)); | ||||
| 
 | ||||
| 			rc = brcmstb_i2c_xfer_bsc_data(dev, tmp_buf, | ||||
| 						       bytes_to_xfer, pmsg); | ||||
| 			if (rc < 0) | ||||
| 				goto out; | ||||
| 
 | ||||
| 			len -=  bytes_to_xfer; | ||||
| 			tmp_buf += bytes_to_xfer; | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	rc = num; | ||||
| out: | ||||
| 	return rc; | ||||
| 
 | ||||
| } | ||||
| 
 | ||||
| static u32 brcmstb_i2c_functionality(struct i2c_adapter *adap) | ||||
| { | ||||
| 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | ||||
| 		| I2C_FUNC_NOSTART | I2C_FUNC_PROTOCOL_MANGLING; | ||||
| } | ||||
| 
 | ||||
| static const struct i2c_algorithm brcmstb_i2c_algo = { | ||||
| 	.master_xfer = brcmstb_i2c_xfer, | ||||
| 	.functionality = brcmstb_i2c_functionality, | ||||
| }; | ||||
| 
 | ||||
| static void brcmstb_i2c_set_bus_speed(struct brcmstb_i2c_dev *dev) | ||||
| { | ||||
| 	int i = 0, num_speeds = ARRAY_SIZE(bsc_clk); | ||||
| 	u32 clk_freq_hz = dev->clk_freq_hz; | ||||
| 
 | ||||
| 	for (i = 0; i < num_speeds; i++) { | ||||
| 		if (bsc_clk[i].hz == clk_freq_hz) { | ||||
| 			dev->bsc_regmap->ctl_reg &= ~(BSC_CTL_REG_SCL_SEL_MASK | ||||
| 						| BSC_CTL_REG_DIV_CLK_MASK); | ||||
| 			dev->bsc_regmap->ctl_reg |= (bsc_clk[i].scl_mask | | ||||
| 						     bsc_clk[i].div_mask); | ||||
| 			bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg); | ||||
| 			break; | ||||
| 		} | ||||
| 	} | ||||
| 
 | ||||
| 	/* in case we did not get find a valid speed */ | ||||
| 	if (i == num_speeds) { | ||||
| 		i = (bsc_readl(dev, ctl_reg) & BSC_CTL_REG_SCL_SEL_MASK) >> | ||||
| 			BSC_CTL_REG_SCL_SEL_SHIFT; | ||||
| 		dev_warn(dev->device, "leaving current clock-frequency @ %dHz\n", | ||||
| 			bsc_clk[i].hz); | ||||
| 	} | ||||
| } | ||||
| 
 | ||||
| static void brcmstb_i2c_set_bsc_reg_defaults(struct brcmstb_i2c_dev *dev) | ||||
| { | ||||
| 	/* 4 byte data register */ | ||||
| 	dev->bsc_regmap->ctlhi_reg = BSC_CTLHI_REG_DATAREG_SIZE_MASK; | ||||
| 	bsc_writel(dev, dev->bsc_regmap->ctlhi_reg, ctlhi_reg); | ||||
| 	/* set bus speed */ | ||||
| 	brcmstb_i2c_set_bus_speed(dev); | ||||
| } | ||||
| 
 | ||||
| static int brcmstb_i2c_probe(struct platform_device *pdev) | ||||
| { | ||||
| 	int rc = 0; | ||||
| 	struct brcmstb_i2c_dev *dev; | ||||
| 	struct i2c_adapter *adap; | ||||
| 	struct resource *iomem; | ||||
| 	const char *int_name; | ||||
| 
 | ||||
| 	/* Allocate memory for private data structure */ | ||||
| 	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); | ||||
| 	if (!dev) | ||||
| 		return -ENOMEM; | ||||
| 
 | ||||
| 	dev->bsc_regmap = devm_kzalloc(&pdev->dev, sizeof(struct bsc_regs *), | ||||
| 				       GFP_KERNEL); | ||||
| 	if (!dev->bsc_regmap) | ||||
| 		return -ENOMEM; | ||||
| 
 | ||||
| 	platform_set_drvdata(pdev, dev); | ||||
| 	dev->device = &pdev->dev; | ||||
| 	init_completion(&dev->done); | ||||
| 
 | ||||
| 	/* Map hardware registers */ | ||||
| 	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||||
| 	dev->base = devm_ioremap_resource(dev->device, iomem); | ||||
| 	if (IS_ERR(dev->base)) { | ||||
| 		rc = -ENOMEM; | ||||
| 		goto probe_errorout; | ||||
| 	} | ||||
| 
 | ||||
| 	rc = of_property_read_string(dev->device->of_node, "interrupt-names", | ||||
| 				     &int_name); | ||||
| 	if (rc < 0) | ||||
| 		int_name = NULL; | ||||
| 
 | ||||
| 	/* Get the interrupt number */ | ||||
| 	dev->irq = platform_get_irq(pdev, 0); | ||||
| 
 | ||||
| 	/* disable the bsc interrupt line */ | ||||
| 	brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE); | ||||
| 
 | ||||
| 	/* register the ISR handler */ | ||||
| 	rc = devm_request_irq(&pdev->dev, dev->irq, brcmstb_i2c_isr, | ||||
| 			      IRQF_SHARED, | ||||
| 			      int_name ? int_name : pdev->name, | ||||
| 			      dev); | ||||
| 
 | ||||
| 	if (rc) { | ||||
| 		dev_dbg(dev->device, "falling back to polling mode"); | ||||
| 		dev->irq = -1; | ||||
| 	} | ||||
| 
 | ||||
| 	if (of_property_read_u32(dev->device->of_node, | ||||
| 				 "clock-frequency", &dev->clk_freq_hz)) { | ||||
| 		dev_warn(dev->device, "setting clock-frequency@%dHz\n", | ||||
| 			 bsc_clk[0].hz); | ||||
| 		dev->clk_freq_hz = bsc_clk[0].hz; | ||||
| 	} | ||||
| 
 | ||||
| 	brcmstb_i2c_set_bsc_reg_defaults(dev); | ||||
| 
 | ||||
| 	/* Add the i2c adapter */ | ||||
| 	adap = &dev->adapter; | ||||
| 	i2c_set_adapdata(adap, dev); | ||||
| 	adap->owner = THIS_MODULE; | ||||
| 	strlcpy(adap->name, "Broadcom STB : ", sizeof(adap->name)); | ||||
| 	if (int_name) | ||||
| 		strlcat(adap->name, int_name, sizeof(adap->name)); | ||||
| 	adap->algo = &brcmstb_i2c_algo; | ||||
| 	adap->dev.parent = &pdev->dev; | ||||
| 	adap->dev.of_node = pdev->dev.of_node; | ||||
| 	rc = i2c_add_adapter(adap); | ||||
| 	if (rc) { | ||||
| 		dev_err(dev->device, "failed to add adapter\n"); | ||||
| 		goto probe_errorout; | ||||
| 	} | ||||
| 
 | ||||
| 	dev_info(dev->device, "%s@%dhz registered in %s mode\n", | ||||
| 		 int_name ? int_name : " ", dev->clk_freq_hz, | ||||
| 		 (dev->irq >= 0) ? "interrupt" : "polling"); | ||||
| 
 | ||||
| 	return 0; | ||||
| 
 | ||||
| probe_errorout: | ||||
| 	return rc; | ||||
| } | ||||
| 
 | ||||
| static int brcmstb_i2c_remove(struct platform_device *pdev) | ||||
| { | ||||
| 	struct brcmstb_i2c_dev *dev = platform_get_drvdata(pdev); | ||||
| 
 | ||||
| 	i2c_del_adapter(&dev->adapter); | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| #ifdef CONFIG_PM_SLEEP | ||||
| static int brcmstb_i2c_suspend(struct device *dev) | ||||
| { | ||||
| 	struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev); | ||||
| 
 | ||||
| 	i2c_lock_adapter(&i2c_dev->adapter); | ||||
| 	i2c_dev->is_suspended = true; | ||||
| 	i2c_unlock_adapter(&i2c_dev->adapter); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| 
 | ||||
| static int brcmstb_i2c_resume(struct device *dev) | ||||
| { | ||||
| 	struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev); | ||||
| 
 | ||||
| 	i2c_lock_adapter(&i2c_dev->adapter); | ||||
| 	brcmstb_i2c_set_bsc_reg_defaults(i2c_dev); | ||||
| 	i2c_dev->is_suspended = false; | ||||
| 	i2c_unlock_adapter(&i2c_dev->adapter); | ||||
| 
 | ||||
| 	return 0; | ||||
| } | ||||
| #endif | ||||
| 
 | ||||
| static SIMPLE_DEV_PM_OPS(brcmstb_i2c_pm, brcmstb_i2c_suspend, | ||||
| 			 brcmstb_i2c_resume); | ||||
| 
 | ||||
| static const struct of_device_id brcmstb_i2c_of_match[] = { | ||||
| 	{.compatible = "brcm,brcmstb-i2c"}, | ||||
| 	{}, | ||||
| }; | ||||
| MODULE_DEVICE_TABLE(of, brcmstb_i2c_of_match); | ||||
| 
 | ||||
| static struct platform_driver brcmstb_i2c_driver = { | ||||
| 	.driver = { | ||||
| 		   .name = "brcmstb-i2c", | ||||
| 		   .of_match_table = brcmstb_i2c_of_match, | ||||
| 		   .pm = &brcmstb_i2c_pm, | ||||
| 		   }, | ||||
| 	.probe = brcmstb_i2c_probe, | ||||
| 	.remove = brcmstb_i2c_remove, | ||||
| }; | ||||
| module_platform_driver(brcmstb_i2c_driver); | ||||
| 
 | ||||
| MODULE_AUTHOR("Kamal Dasu <kdasu@broadcom.com>"); | ||||
| MODULE_DESCRIPTION("Broadcom Settop I2C Driver"); | ||||
| MODULE_LICENSE("GPL v2"); | ||||
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		Reference in a new issue
	
	 Kamal Dasu
						Kamal Dasu