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	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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										28
									
								
								Documentation/devicetree/bindings/i2c/i2c-brcmstb.txt
									
									
									
									
									
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										28
									
								
								Documentation/devicetree/bindings/i2c/i2c-brcmstb.txt
									
									
									
									
									
										Normal file
									
								
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			@ -0,0 +1,28 @@
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Broadcom stb bsc iic master controller
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Required properties:
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- compatible: should be "brcm,brcmstb-i2c"
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- clock-frequency: 32-bit decimal value of iic master clock freqency in Hz
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		   valid values are 375000, 390000, 187500, 200000
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		   93750, 97500, 46875 and 50000
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- reg: specifies the base physical address and size of the registers
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Optional properties :
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- interrupt-parent: specifies the phandle to the parent interrupt controller
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  this one is cascaded from
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- interrupts: specifies the interrupt number, the irq line to be used
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- interrupt-names: Interrupt name string
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Example:
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bsca: i2c@f0406200 {
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      clock-frequency = <390000>;
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      compatible = "brcm,brcmstb-i2c";
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      interrupt-parent = <&irq0_intc>;
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      reg = <0xf0406200 0x58>;
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      interrupts = <0x18>;
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      interrupt-names = "upg_bsca";
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};
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			@ -392,6 +392,16 @@ config I2C_BCM_KONA
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	  If you do not need KONA I2C interface, say N.
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config I2C_BRCMSTB
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	tristate "BRCM Settop I2C controller"
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	depends on ARCH_BRCMSTB || COMPILE_TEST
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	default y
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	help
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	  If you say yes to this option, support will be included for the
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	  I2C interface on the Broadcom Settop SoCs.
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	  If you do not need I2C interface, say N.
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config I2C_BLACKFIN_TWI
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	tristate "Blackfin TWI I2C support"
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	depends on BLACKFIN
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			@ -106,6 +106,7 @@ obj-$(CONFIG_I2C_VIPERBOARD)	+= i2c-viperboard.o
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# Other I2C/SMBus bus drivers
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obj-$(CONFIG_I2C_ACORN)		+= i2c-acorn.o
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obj-$(CONFIG_I2C_BCM_KONA)	+= i2c-bcm-kona.o
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obj-$(CONFIG_I2C_BRCMSTB)	+= i2c-brcmstb.o
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obj-$(CONFIG_I2C_CROS_EC_TUNNEL)	+= i2c-cros-ec-tunnel.o
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obj-$(CONFIG_I2C_ELEKTOR)	+= i2c-elektor.o
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obj-$(CONFIG_I2C_OPAL)		+= i2c-opal.o
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										694
									
								
								drivers/i2c/busses/i2c-brcmstb.c
									
									
									
									
									
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										694
									
								
								drivers/i2c/busses/i2c-brcmstb.c
									
									
									
									
									
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			@ -0,0 +1,694 @@
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/*
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 * Copyright (C) 2014 Broadcom Corporation
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 *
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 * This program is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU General Public License as
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 * published by the Free Software Foundation version 2.
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 *
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 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
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 * kind, whether express or implied; without even the implied warranty
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 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 */
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/device.h>
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#include <linux/i2c.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/platform_device.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/version.h>
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#define N_DATA_REGS					8
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#define N_DATA_BYTES					(N_DATA_REGS * 4)
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/* BSC count register field definitions */
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#define BSC_CNT_REG1_MASK				0x0000003f
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#define BSC_CNT_REG1_SHIFT				0
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#define BSC_CNT_REG2_MASK				0x00000fc0
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#define BSC_CNT_REG2_SHIFT				6
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/* BSC CTL register field definitions */
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#define BSC_CTL_REG_DTF_MASK				0x00000003
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#define BSC_CTL_REG_SCL_SEL_MASK			0x00000030
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#define BSC_CTL_REG_SCL_SEL_SHIFT			4
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#define BSC_CTL_REG_INT_EN_MASK				0x00000040
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#define BSC_CTL_REG_INT_EN_SHIFT			6
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#define BSC_CTL_REG_DIV_CLK_MASK			0x00000080
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/* BSC_IIC_ENABLE r/w enable and interrupt field defintions */
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#define BSC_IIC_EN_RESTART_MASK				0x00000040
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#define BSC_IIC_EN_NOSTART_MASK				0x00000020
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#define BSC_IIC_EN_NOSTOP_MASK				0x00000010
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#define BSC_IIC_EN_NOACK_MASK				0x00000004
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#define BSC_IIC_EN_INTRP_MASK				0x00000002
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#define BSC_IIC_EN_ENABLE_MASK				0x00000001
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/* BSC_CTLHI control register field definitions */
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#define BSC_CTLHI_REG_INPUT_SWITCHING_LEVEL_MASK	0x00000080
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#define BSC_CTLHI_REG_DATAREG_SIZE_MASK			0x00000040
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#define BSC_CTLHI_REG_IGNORE_ACK_MASK			0x00000002
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#define BSC_CTLHI_REG_WAIT_DIS_MASK			0x00000001
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#define I2C_TIMEOUT					100 /* msecs */
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/* Condition mask used for non combined transfer */
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#define COND_RESTART		BSC_IIC_EN_RESTART_MASK
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#define COND_NOSTART		BSC_IIC_EN_NOSTART_MASK
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#define COND_NOSTOP		BSC_IIC_EN_NOSTOP_MASK
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#define COND_START_STOP		(COND_RESTART | COND_NOSTART | COND_NOSTOP)
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/* BSC data transfer direction */
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#define DTF_WR_MASK		0x00000000
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#define DTF_RD_MASK		0x00000001
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/* BSC data transfer direction combined format */
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#define DTF_RD_WR_MASK		0x00000002
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#define DTF_WR_RD_MASK		0x00000003
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#define INT_ENABLE		true
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#define INT_DISABLE		false
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/* BSC block register map structure to cache fields to be written */
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struct bsc_regs {
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	u32	chip_address;           /* slave address */
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	u32	data_in[N_DATA_REGS];   /* tx data buffer*/
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	u32	cnt_reg;		/* rx/tx data length */
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	u32	ctl_reg;		/* control register */
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	u32	iic_enable;		/* xfer enable and status */
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	u32	data_out[N_DATA_REGS];  /* rx data buffer */
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	u32	ctlhi_reg;		/* more control fields */
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	u32	scl_param;		/* reserved */
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};
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struct bsc_clk_param {
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	u32 hz;
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	u32 scl_mask;
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	u32 div_mask;
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};
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enum bsc_xfer_cmd {
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	CMD_WR,
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	CMD_RD,
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	CMD_WR_NOACK,
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	CMD_RD_NOACK,
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};
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static char const *cmd_string[] = {
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	[CMD_WR] = "WR",
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	[CMD_RD] = "RD",
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	[CMD_WR_NOACK] = "WR NOACK",
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	[CMD_RD_NOACK] = "RD NOACK",
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};
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enum bus_speeds {
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	SPD_375K,
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	SPD_390K,
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	SPD_187K,
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	SPD_200K,
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	SPD_93K,
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	SPD_97K,
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	SPD_46K,
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	SPD_50K
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};
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static const struct bsc_clk_param bsc_clk[] = {
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	[SPD_375K] = {
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		.hz = 375000,
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		.scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT,
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		.div_mask = 0
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	},
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	[SPD_390K] = {
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		.hz = 390000,
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		.scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT,
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		.div_mask = 0
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	},
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	[SPD_187K] = {
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		.hz = 187500,
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		.scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT,
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		.div_mask = 0
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	},
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	[SPD_200K] = {
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		.hz = 200000,
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		.scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT,
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		.div_mask = 0
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	},
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	[SPD_93K]  = {
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		.hz = 93750,
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		.scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT,
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		.div_mask = BSC_CTL_REG_DIV_CLK_MASK
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	},
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	[SPD_97K]  = {
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		.hz = 97500,
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		.scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT,
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		.div_mask = BSC_CTL_REG_DIV_CLK_MASK
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	},
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	[SPD_46K]  = {
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		.hz = 46875,
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		.scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT,
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		.div_mask = BSC_CTL_REG_DIV_CLK_MASK
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	},
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	[SPD_50K]  = {
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		.hz = 50000,
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		.scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT,
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		.div_mask = BSC_CTL_REG_DIV_CLK_MASK
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	}
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};
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struct brcmstb_i2c_dev {
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	struct device *device;
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	void __iomem *base;
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	void __iomem *irq_base;
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	int irq;
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	struct bsc_regs *bsc_regmap;
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	struct i2c_adapter adapter;
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	struct completion done;
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	bool is_suspended;
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	u32 clk_freq_hz;
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};
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/* register accessors for both be and le cpu arch */
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#ifdef CONFIG_CPU_BIG_ENDIAN
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#define __bsc_readl(_reg) ioread32be(_reg)
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#define __bsc_writel(_val, _reg) iowrite32be(_val, _reg)
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#else
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#define __bsc_readl(_reg) ioread32(_reg)
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#define __bsc_writel(_val, _reg) iowrite32(_val, _reg)
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#endif
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#define bsc_readl(_dev, _reg)						\
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	__bsc_readl(_dev->base + offsetof(struct bsc_regs, _reg))
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#define bsc_writel(_dev, _val, _reg)					\
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	__bsc_writel(_val, _dev->base + offsetof(struct bsc_regs, _reg))
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static void brcmstb_i2c_enable_disable_irq(struct brcmstb_i2c_dev *dev,
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					   bool int_en)
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{
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	if (int_en)
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		/* Enable BSC  CTL interrupt line */
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		dev->bsc_regmap->ctl_reg |= BSC_CTL_REG_INT_EN_MASK;
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	else
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		/* Disable BSC CTL interrupt line */
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		dev->bsc_regmap->ctl_reg &= ~BSC_CTL_REG_INT_EN_MASK;
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	barrier();
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	bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg);
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}
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static irqreturn_t brcmstb_i2c_isr(int irq, void *devid)
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{
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	struct brcmstb_i2c_dev *dev = devid;
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	u32 status_bsc_ctl = bsc_readl(dev, ctl_reg);
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	u32 status_iic_intrp = bsc_readl(dev, iic_enable);
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	dev_dbg(dev->device, "isr CTL_REG %x IIC_EN %x\n",
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		status_bsc_ctl, status_iic_intrp);
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	if (!(status_bsc_ctl & BSC_CTL_REG_INT_EN_MASK))
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		return IRQ_NONE;
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	brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE);
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	complete_all(&dev->done);
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	dev_dbg(dev->device, "isr handled");
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	return IRQ_HANDLED;
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}
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/* Wait for device to be ready */
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static int brcmstb_i2c_wait_if_busy(struct brcmstb_i2c_dev *dev)
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{
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	unsigned long timeout = jiffies + msecs_to_jiffies(I2C_TIMEOUT);
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	while ((bsc_readl(dev, iic_enable) & BSC_IIC_EN_INTRP_MASK)) {
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		if (time_after(jiffies, timeout))
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			return -ETIMEDOUT;
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		cpu_relax();
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	}
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	return 0;
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}
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/* i2c xfer completion function, handles both irq and polling mode */
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static int brcmstb_i2c_wait_for_completion(struct brcmstb_i2c_dev *dev)
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{
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	int ret = 0;
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	unsigned long timeout = msecs_to_jiffies(I2C_TIMEOUT);
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	if (dev->irq >= 0) {
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		if (!wait_for_completion_timeout(&dev->done, timeout))
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			ret = -ETIMEDOUT;
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	} else {
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		/* we are in polling mode */
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		u32 bsc_intrp;
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		unsigned long time_left = jiffies + timeout;
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		do {
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			bsc_intrp = bsc_readl(dev, iic_enable) &
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				BSC_IIC_EN_INTRP_MASK;
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			if (time_after(jiffies, time_left)) {
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				ret = -ETIMEDOUT;
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				break;
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			}
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			cpu_relax();
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		} while (!bsc_intrp);
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	}
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	if (dev->irq < 0 || ret == -ETIMEDOUT)
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		brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE);
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	return ret;
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}
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/* Set xfer START/STOP conditions for subsequent transfer */
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static void brcmstb_set_i2c_start_stop(struct brcmstb_i2c_dev *dev,
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				       u32 cond_flag)
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{
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	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");
 | 
			
		||||
		Loading…
	
		Reference in a new issue