 ebba48b702
			
		
	
	
	ebba48b702
	
	
	
		
			
			Of_node_put supports NULL as its argument, so the initial test is not necessary. Suggested by Uwe Kleine-König. The semantic patch that fixes this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression e; @@ -if (e) of_node_put(e); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
		
			
				
	
	
		
			828 lines
		
	
	
	
		
			21 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			828 lines
		
	
	
	
		
			21 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * (C) Copyright 2003-2004
 | |
|  * Humboldt Solutions Ltd, adrian@humboldt.co.uk.
 | |
| 
 | |
|  * This is a combined i2c adapter and algorithm driver for the
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|  * MPC107/Tsi107 PowerPC northbridge and processors that include
 | |
|  * the same I2C unit (8240, 8245, 85xx).
 | |
|  *
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|  * Release 0.8
 | |
|  *
 | |
|  * This file is licensed under the terms of the GNU General Public
 | |
|  * License version 2. This program is licensed "as is" without any
 | |
|  * warranty of any kind, whether express or implied.
 | |
|  */
 | |
| 
 | |
| #include <linux/kernel.h>
 | |
| #include <linux/module.h>
 | |
| #include <linux/sched.h>
 | |
| #include <linux/of_address.h>
 | |
| #include <linux/of_irq.h>
 | |
| #include <linux/of_platform.h>
 | |
| #include <linux/slab.h>
 | |
| 
 | |
| #include <linux/clk.h>
 | |
| #include <linux/io.h>
 | |
| #include <linux/fsl_devices.h>
 | |
| #include <linux/i2c.h>
 | |
| #include <linux/interrupt.h>
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| #include <linux/delay.h>
 | |
| 
 | |
| #include <asm/mpc52xx.h>
 | |
| #include <sysdev/fsl_soc.h>
 | |
| 
 | |
| #define DRV_NAME "mpc-i2c"
 | |
| 
 | |
| #define MPC_I2C_CLOCK_LEGACY   0
 | |
| #define MPC_I2C_CLOCK_PRESERVE (~0U)
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| 
 | |
| #define MPC_I2C_FDR   0x04
 | |
| #define MPC_I2C_CR    0x08
 | |
| #define MPC_I2C_SR    0x0c
 | |
| #define MPC_I2C_DR    0x10
 | |
| #define MPC_I2C_DFSRR 0x14
 | |
| 
 | |
| #define CCR_MEN  0x80
 | |
| #define CCR_MIEN 0x40
 | |
| #define CCR_MSTA 0x20
 | |
| #define CCR_MTX  0x10
 | |
| #define CCR_TXAK 0x08
 | |
| #define CCR_RSTA 0x04
 | |
| 
 | |
| #define CSR_MCF  0x80
 | |
| #define CSR_MAAS 0x40
 | |
| #define CSR_MBB  0x20
 | |
| #define CSR_MAL  0x10
 | |
| #define CSR_SRW  0x04
 | |
| #define CSR_MIF  0x02
 | |
| #define CSR_RXAK 0x01
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| 
 | |
| struct mpc_i2c {
 | |
| 	struct device *dev;
 | |
| 	void __iomem *base;
 | |
| 	u32 interrupt;
 | |
| 	wait_queue_head_t queue;
 | |
| 	struct i2c_adapter adap;
 | |
| 	int irq;
 | |
| 	u32 real_clk;
 | |
| #ifdef CONFIG_PM_SLEEP
 | |
| 	u8 fdr, dfsrr;
 | |
| #endif
 | |
| 	struct clk *clk_per;
 | |
| };
 | |
| 
 | |
| struct mpc_i2c_divider {
 | |
| 	u16 divider;
 | |
| 	u16 fdr;	/* including dfsrr */
 | |
| };
 | |
| 
 | |
| struct mpc_i2c_data {
 | |
| 	void (*setup)(struct device_node *node, struct mpc_i2c *i2c,
 | |
| 		      u32 clock, u32 prescaler);
 | |
| 	u32 prescaler;
 | |
| };
 | |
| 
 | |
| static inline void writeccr(struct mpc_i2c *i2c, u32 x)
 | |
| {
 | |
| 	writeb(x, i2c->base + MPC_I2C_CR);
 | |
| }
 | |
| 
 | |
| static irqreturn_t mpc_i2c_isr(int irq, void *dev_id)
 | |
| {
 | |
| 	struct mpc_i2c *i2c = dev_id;
 | |
| 	if (readb(i2c->base + MPC_I2C_SR) & CSR_MIF) {
 | |
| 		/* Read again to allow register to stabilise */
 | |
| 		i2c->interrupt = readb(i2c->base + MPC_I2C_SR);
 | |
| 		writeb(0, i2c->base + MPC_I2C_SR);
 | |
| 		wake_up(&i2c->queue);
 | |
| 	}
 | |
| 	return IRQ_HANDLED;
 | |
| }
 | |
| 
 | |
| /* Sometimes 9th clock pulse isn't generated, and slave doesn't release
 | |
|  * the bus, because it wants to send ACK.
 | |
|  * Following sequence of enabling/disabling and sending start/stop generates
 | |
|  * the 9 pulses, so it's all OK.
 | |
|  */
 | |
| static void mpc_i2c_fixup(struct mpc_i2c *i2c)
 | |
| {
 | |
| 	int k;
 | |
| 	u32 delay_val = 1000000 / i2c->real_clk + 1;
 | |
| 
 | |
| 	if (delay_val < 2)
 | |
| 		delay_val = 2;
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| 
 | |
| 	for (k = 9; k; k--) {
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| 		writeccr(i2c, 0);
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| 		writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN);
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| 		readb(i2c->base + MPC_I2C_DR);
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| 		writeccr(i2c, CCR_MEN);
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| 		udelay(delay_val << 1);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
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| {
 | |
| 	unsigned long orig_jiffies = jiffies;
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| 	u32 x;
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| 	int result = 0;
 | |
| 
 | |
| 	if (!i2c->irq) {
 | |
| 		while (!(readb(i2c->base + MPC_I2C_SR) & CSR_MIF)) {
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| 			schedule();
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| 			if (time_after(jiffies, orig_jiffies + timeout)) {
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| 				dev_dbg(i2c->dev, "timeout\n");
 | |
| 				writeccr(i2c, 0);
 | |
| 				result = -EIO;
 | |
| 				break;
 | |
| 			}
 | |
| 		}
 | |
| 		x = readb(i2c->base + MPC_I2C_SR);
 | |
| 		writeb(0, i2c->base + MPC_I2C_SR);
 | |
| 	} else {
 | |
| 		/* Interrupt mode */
 | |
| 		result = wait_event_timeout(i2c->queue,
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| 			(i2c->interrupt & CSR_MIF), timeout);
 | |
| 
 | |
| 		if (unlikely(!(i2c->interrupt & CSR_MIF))) {
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| 			dev_dbg(i2c->dev, "wait timeout\n");
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| 			writeccr(i2c, 0);
 | |
| 			result = -ETIMEDOUT;
 | |
| 		}
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| 
 | |
| 		x = i2c->interrupt;
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| 		i2c->interrupt = 0;
 | |
| 	}
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| 
 | |
| 	if (result < 0)
 | |
| 		return result;
 | |
| 
 | |
| 	if (!(x & CSR_MCF)) {
 | |
| 		dev_dbg(i2c->dev, "unfinished\n");
 | |
| 		return -EIO;
 | |
| 	}
 | |
| 
 | |
| 	if (x & CSR_MAL) {
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| 		dev_dbg(i2c->dev, "MAL\n");
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| 		return -EIO;
 | |
| 	}
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| 
 | |
| 	if (writing && (x & CSR_RXAK)) {
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| 		dev_dbg(i2c->dev, "No RXAK\n");
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| 		/* generate stop */
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| 		writeccr(i2c, CCR_MEN);
 | |
| 		return -EIO;
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| #if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x)
 | |
| static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = {
 | |
| 	{20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23},
 | |
| 	{28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02},
 | |
| 	{36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28},
 | |
| 	{52, 0x63}, {56, 0x29}, {60, 0x41}, {64, 0x2a},
 | |
| 	{68, 0x07}, {72, 0x2b}, {80, 0x2c}, {88, 0x09},
 | |
| 	{96, 0x2d}, {104, 0x0a}, {112, 0x2e}, {120, 0x81},
 | |
| 	{128, 0x2f}, {136, 0x47}, {144, 0x0c}, {160, 0x30},
 | |
| 	{176, 0x49}, {192, 0x31}, {208, 0x4a}, {224, 0x32},
 | |
| 	{240, 0x0f}, {256, 0x33}, {272, 0x87}, {288, 0x10},
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| 	{320, 0x34}, {352, 0x89}, {384, 0x35}, {416, 0x8a},
 | |
| 	{448, 0x36}, {480, 0x13}, {512, 0x37}, {576, 0x14},
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| 	{640, 0x38}, {768, 0x39}, {896, 0x3a}, {960, 0x17},
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| 	{1024, 0x3b}, {1152, 0x18}, {1280, 0x3c}, {1536, 0x3d},
 | |
| 	{1792, 0x3e}, {1920, 0x1b}, {2048, 0x3f}, {2304, 0x1c},
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| 	{2560, 0x1d}, {3072, 0x1e}, {3584, 0x7e}, {3840, 0x1f},
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| 	{4096, 0x7f}, {4608, 0x5c}, {5120, 0x5d}, {6144, 0x5e},
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| 	{7168, 0xbe}, {7680, 0x5f}, {8192, 0xbf}, {9216, 0x9c},
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| 	{10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f}
 | |
| };
 | |
| 
 | |
| static int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
 | |
| 					  int prescaler, u32 *real_clk)
 | |
| {
 | |
| 	const struct mpc_i2c_divider *div = NULL;
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| 	unsigned int pvr = mfspr(SPRN_PVR);
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| 	u32 divider;
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| 	int i;
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| 
 | |
| 	if (clock == MPC_I2C_CLOCK_LEGACY) {
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| 		/* see below - default fdr = 0x3f -> div = 2048 */
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| 		*real_clk = mpc5xxx_get_bus_frequency(node) / 2048;
 | |
| 		return -EINVAL;
 | |
| 	}
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| 
 | |
| 	/* Determine divider value */
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| 	divider = mpc5xxx_get_bus_frequency(node) / clock;
 | |
| 
 | |
| 	/*
 | |
| 	 * We want to choose an FDR/DFSR that generates an I2C bus speed that
 | |
| 	 * is equal to or lower than the requested speed.
 | |
| 	 */
 | |
| 	for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) {
 | |
| 		div = &mpc_i2c_dividers_52xx[i];
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| 		/* Old MPC5200 rev A CPUs do not support the high bits */
 | |
| 		if (div->fdr & 0xc0 && pvr == 0x80822011)
 | |
| 			continue;
 | |
| 		if (div->divider >= divider)
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| 			break;
 | |
| 	}
 | |
| 
 | |
| 	*real_clk = mpc5xxx_get_bus_frequency(node) / div->divider;
 | |
| 	return (int)div->fdr;
 | |
| }
 | |
| 
 | |
| static void mpc_i2c_setup_52xx(struct device_node *node,
 | |
| 					 struct mpc_i2c *i2c,
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| 					 u32 clock, u32 prescaler)
 | |
| {
 | |
| 	int ret, fdr;
 | |
| 
 | |
| 	if (clock == MPC_I2C_CLOCK_PRESERVE) {
 | |
| 		dev_dbg(i2c->dev, "using fdr %d\n",
 | |
| 			readb(i2c->base + MPC_I2C_FDR));
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler, &i2c->real_clk);
 | |
| 	fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */
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| 
 | |
| 	writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
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| 
 | |
| 	if (ret >= 0)
 | |
| 		dev_info(i2c->dev, "clock %u Hz (fdr=%d)\n", i2c->real_clk,
 | |
| 			 fdr);
 | |
| }
 | |
| #else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */
 | |
| static void mpc_i2c_setup_52xx(struct device_node *node,
 | |
| 					 struct mpc_i2c *i2c,
 | |
| 					 u32 clock, u32 prescaler)
 | |
| {
 | |
| }
 | |
| #endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */
 | |
| 
 | |
| #ifdef CONFIG_PPC_MPC512x
 | |
| static void mpc_i2c_setup_512x(struct device_node *node,
 | |
| 					 struct mpc_i2c *i2c,
 | |
| 					 u32 clock, u32 prescaler)
 | |
| {
 | |
| 	struct device_node *node_ctrl;
 | |
| 	void __iomem *ctrl;
 | |
| 	const u32 *pval;
 | |
| 	u32 idx;
 | |
| 
 | |
| 	/* Enable I2C interrupts for mpc5121 */
 | |
| 	node_ctrl = of_find_compatible_node(NULL, NULL,
 | |
| 					    "fsl,mpc5121-i2c-ctrl");
 | |
| 	if (node_ctrl) {
 | |
| 		ctrl = of_iomap(node_ctrl, 0);
 | |
| 		if (ctrl) {
 | |
| 			/* Interrupt enable bits for i2c-0/1/2: bit 24/26/28 */
 | |
| 			pval = of_get_property(node, "reg", NULL);
 | |
| 			idx = (*pval & 0xff) / 0x20;
 | |
| 			setbits32(ctrl, 1 << (24 + idx * 2));
 | |
| 			iounmap(ctrl);
 | |
| 		}
 | |
| 		of_node_put(node_ctrl);
 | |
| 	}
 | |
| 
 | |
| 	/* The clock setup for the 52xx works also fine for the 512x */
 | |
| 	mpc_i2c_setup_52xx(node, i2c, clock, prescaler);
 | |
| }
 | |
| #else /* CONFIG_PPC_MPC512x */
 | |
| static void mpc_i2c_setup_512x(struct device_node *node,
 | |
| 					 struct mpc_i2c *i2c,
 | |
| 					 u32 clock, u32 prescaler)
 | |
| {
 | |
| }
 | |
| #endif /* CONFIG_PPC_MPC512x */
 | |
| 
 | |
| #ifdef CONFIG_FSL_SOC
 | |
| static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = {
 | |
| 	{160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123},
 | |
| 	{288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102},
 | |
| 	{416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127},
 | |
| 	{544, 0x0b03}, {576, 0x0104}, {608, 0x1603}, {640, 0x0105},
 | |
| 	{672, 0x2003}, {704, 0x0b05}, {736, 0x2b03}, {768, 0x0106},
 | |
| 	{800, 0x3603}, {832, 0x0b06}, {896, 0x012a}, {960, 0x0107},
 | |
| 	{1024, 0x012b}, {1088, 0x1607}, {1152, 0x0108}, {1216, 0x2b07},
 | |
| 	{1280, 0x0109}, {1408, 0x1609}, {1536, 0x010a}, {1664, 0x160a},
 | |
| 	{1792, 0x012e}, {1920, 0x010b}, {2048, 0x012f}, {2176, 0x2b0b},
 | |
| 	{2304, 0x010c}, {2560, 0x010d}, {2816, 0x2b0d}, {3072, 0x010e},
 | |
| 	{3328, 0x2b0e}, {3584, 0x0132}, {3840, 0x010f}, {4096, 0x0133},
 | |
| 	{4608, 0x0110}, {5120, 0x0111}, {6144, 0x0112}, {7168, 0x0136},
 | |
| 	{7680, 0x0113}, {8192, 0x0137}, {9216, 0x0114}, {10240, 0x0115},
 | |
| 	{12288, 0x0116}, {14336, 0x013a}, {15360, 0x0117}, {16384, 0x013b},
 | |
| 	{18432, 0x0118}, {20480, 0x0119}, {24576, 0x011a}, {28672, 0x013e},
 | |
| 	{30720, 0x011b}, {32768, 0x013f}, {36864, 0x011c}, {40960, 0x011d},
 | |
| 	{49152, 0x011e}, {61440, 0x011f}
 | |
| };
 | |
| 
 | |
| static u32 mpc_i2c_get_sec_cfg_8xxx(void)
 | |
| {
 | |
| 	struct device_node *node = NULL;
 | |
| 	u32 __iomem *reg;
 | |
| 	u32 val = 0;
 | |
| 
 | |
| 	node = of_find_node_by_name(NULL, "global-utilities");
 | |
| 	if (node) {
 | |
| 		const u32 *prop = of_get_property(node, "reg", NULL);
 | |
| 		if (prop) {
 | |
| 			/*
 | |
| 			 * Map and check POR Device Status Register 2
 | |
| 			 * (PORDEVSR2) at 0xE0014
 | |
| 			 */
 | |
| 			reg = ioremap(get_immrbase() + *prop + 0x14, 0x4);
 | |
| 			if (!reg)
 | |
| 				printk(KERN_ERR
 | |
| 				       "Error: couldn't map PORDEVSR2\n");
 | |
| 			else
 | |
| 				val = in_be32(reg) & 0x00000080; /* sec-cfg */
 | |
| 			iounmap(reg);
 | |
| 		}
 | |
| 	}
 | |
| 	of_node_put(node);
 | |
| 
 | |
| 	return val;
 | |
| }
 | |
| 
 | |
| static int mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
 | |
| 					  u32 prescaler, u32 *real_clk)
 | |
| {
 | |
| 	const struct mpc_i2c_divider *div = NULL;
 | |
| 	u32 divider;
 | |
| 	int i;
 | |
| 
 | |
| 	if (clock == MPC_I2C_CLOCK_LEGACY) {
 | |
| 		/* see below - default fdr = 0x1031 -> div = 16 * 3072 */
 | |
| 		*real_clk = fsl_get_sys_freq() / prescaler / (16 * 3072);
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	/* Determine proper divider value */
 | |
| 	if (of_device_is_compatible(node, "fsl,mpc8544-i2c"))
 | |
| 		prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2;
 | |
| 	if (!prescaler)
 | |
| 		prescaler = 1;
 | |
| 
 | |
| 	divider = fsl_get_sys_freq() / clock / prescaler;
 | |
| 
 | |
| 	pr_debug("I2C: src_clock=%d clock=%d divider=%d\n",
 | |
| 		 fsl_get_sys_freq(), clock, divider);
 | |
| 
 | |
| 	/*
 | |
| 	 * We want to choose an FDR/DFSR that generates an I2C bus speed that
 | |
| 	 * is equal to or lower than the requested speed.
 | |
| 	 */
 | |
| 	for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_8xxx); i++) {
 | |
| 		div = &mpc_i2c_dividers_8xxx[i];
 | |
| 		if (div->divider >= divider)
 | |
| 			break;
 | |
| 	}
 | |
| 
 | |
| 	*real_clk = fsl_get_sys_freq() / prescaler / div->divider;
 | |
| 	return div ? (int)div->fdr : -EINVAL;
 | |
| }
 | |
| 
 | |
| static void mpc_i2c_setup_8xxx(struct device_node *node,
 | |
| 					 struct mpc_i2c *i2c,
 | |
| 					 u32 clock, u32 prescaler)
 | |
| {
 | |
| 	int ret, fdr;
 | |
| 
 | |
| 	if (clock == MPC_I2C_CLOCK_PRESERVE) {
 | |
| 		dev_dbg(i2c->dev, "using dfsrr %d, fdr %d\n",
 | |
| 			readb(i2c->base + MPC_I2C_DFSRR),
 | |
| 			readb(i2c->base + MPC_I2C_FDR));
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler, &i2c->real_clk);
 | |
| 	fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */
 | |
| 
 | |
| 	writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
 | |
| 	writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR);
 | |
| 
 | |
| 	if (ret >= 0)
 | |
| 		dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n",
 | |
| 			 i2c->real_clk, fdr >> 8, fdr & 0xff);
 | |
| }
 | |
| 
 | |
| #else /* !CONFIG_FSL_SOC */
 | |
| static void mpc_i2c_setup_8xxx(struct device_node *node,
 | |
| 					 struct mpc_i2c *i2c,
 | |
| 					 u32 clock, u32 prescaler)
 | |
| {
 | |
| }
 | |
| #endif /* CONFIG_FSL_SOC */
 | |
| 
 | |
| static void mpc_i2c_start(struct mpc_i2c *i2c)
 | |
| {
 | |
| 	/* Clear arbitration */
 | |
| 	writeb(0, i2c->base + MPC_I2C_SR);
 | |
| 	/* Start with MEN */
 | |
| 	writeccr(i2c, CCR_MEN);
 | |
| }
 | |
| 
 | |
| static void mpc_i2c_stop(struct mpc_i2c *i2c)
 | |
| {
 | |
| 	writeccr(i2c, CCR_MEN);
 | |
| }
 | |
| 
 | |
| static int mpc_write(struct mpc_i2c *i2c, int target,
 | |
| 		     const u8 *data, int length, int restart)
 | |
| {
 | |
| 	int i, result;
 | |
| 	unsigned timeout = i2c->adap.timeout;
 | |
| 	u32 flags = restart ? CCR_RSTA : 0;
 | |
| 
 | |
| 	/* Start as master */
 | |
| 	writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags);
 | |
| 	/* Write target byte */
 | |
| 	writeb((target << 1), i2c->base + MPC_I2C_DR);
 | |
| 
 | |
| 	result = i2c_wait(i2c, timeout, 1);
 | |
| 	if (result < 0)
 | |
| 		return result;
 | |
| 
 | |
| 	for (i = 0; i < length; i++) {
 | |
| 		/* Write data byte */
 | |
| 		writeb(data[i], i2c->base + MPC_I2C_DR);
 | |
| 
 | |
| 		result = i2c_wait(i2c, timeout, 1);
 | |
| 		if (result < 0)
 | |
| 			return result;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int mpc_read(struct mpc_i2c *i2c, int target,
 | |
| 		    u8 *data, int length, int restart, bool recv_len)
 | |
| {
 | |
| 	unsigned timeout = i2c->adap.timeout;
 | |
| 	int i, result;
 | |
| 	u32 flags = restart ? CCR_RSTA : 0;
 | |
| 
 | |
| 	/* Switch to read - restart */
 | |
| 	writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags);
 | |
| 	/* Write target address byte - this time with the read flag set */
 | |
| 	writeb((target << 1) | 1, i2c->base + MPC_I2C_DR);
 | |
| 
 | |
| 	result = i2c_wait(i2c, timeout, 1);
 | |
| 	if (result < 0)
 | |
| 		return result;
 | |
| 
 | |
| 	if (length) {
 | |
| 		if (length == 1 && !recv_len)
 | |
| 			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);
 | |
| 		else
 | |
| 			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA);
 | |
| 		/* Dummy read */
 | |
| 		readb(i2c->base + MPC_I2C_DR);
 | |
| 	}
 | |
| 
 | |
| 	for (i = 0; i < length; i++) {
 | |
| 		u8 byte;
 | |
| 
 | |
| 		result = i2c_wait(i2c, timeout, 0);
 | |
| 		if (result < 0)
 | |
| 			return result;
 | |
| 
 | |
| 		/*
 | |
| 		 * For block reads, we have to know the total length (1st byte)
 | |
| 		 * before we can determine if we are done.
 | |
| 		 */
 | |
| 		if (i || !recv_len) {
 | |
| 			/* Generate txack on next to last byte */
 | |
| 			if (i == length - 2)
 | |
| 				writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
 | |
| 					 | CCR_TXAK);
 | |
| 			/* Do not generate stop on last byte */
 | |
| 			if (i == length - 1)
 | |
| 				writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
 | |
| 					 | CCR_MTX);
 | |
| 		}
 | |
| 
 | |
| 		byte = readb(i2c->base + MPC_I2C_DR);
 | |
| 
 | |
| 		/*
 | |
| 		 * Adjust length if first received byte is length.
 | |
| 		 * The length is 1 length byte plus actually data length
 | |
| 		 */
 | |
| 		if (i == 0 && recv_len) {
 | |
| 			if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX)
 | |
| 				return -EPROTO;
 | |
| 			length += byte;
 | |
| 			/*
 | |
| 			 * For block reads, generate txack here if data length
 | |
| 			 * is 1 byte (total length is 2 bytes).
 | |
| 			 */
 | |
| 			if (length == 2)
 | |
| 				writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA
 | |
| 					 | CCR_TXAK);
 | |
| 		}
 | |
| 		data[i] = byte;
 | |
| 	}
 | |
| 
 | |
| 	return length;
 | |
| }
 | |
| 
 | |
| static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 | |
| {
 | |
| 	struct i2c_msg *pmsg;
 | |
| 	int i;
 | |
| 	int ret = 0;
 | |
| 	unsigned long orig_jiffies = jiffies;
 | |
| 	struct mpc_i2c *i2c = i2c_get_adapdata(adap);
 | |
| 
 | |
| 	mpc_i2c_start(i2c);
 | |
| 
 | |
| 	/* Allow bus up to 1s to become not busy */
 | |
| 	while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) {
 | |
| 		if (signal_pending(current)) {
 | |
| 			dev_dbg(i2c->dev, "Interrupted\n");
 | |
| 			writeccr(i2c, 0);
 | |
| 			return -EINTR;
 | |
| 		}
 | |
| 		if (time_after(jiffies, orig_jiffies + HZ)) {
 | |
| 			u8 status = readb(i2c->base + MPC_I2C_SR);
 | |
| 
 | |
| 			dev_dbg(i2c->dev, "timeout\n");
 | |
| 			if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
 | |
| 				writeb(status & ~CSR_MAL,
 | |
| 				       i2c->base + MPC_I2C_SR);
 | |
| 				mpc_i2c_fixup(i2c);
 | |
| 			}
 | |
| 			return -EIO;
 | |
| 		}
 | |
| 		schedule();
 | |
| 	}
 | |
| 
 | |
| 	for (i = 0; ret >= 0 && i < num; i++) {
 | |
| 		pmsg = &msgs[i];
 | |
| 		dev_dbg(i2c->dev,
 | |
| 			"Doing %s %d bytes to 0x%02x - %d of %d messages\n",
 | |
| 			pmsg->flags & I2C_M_RD ? "read" : "write",
 | |
| 			pmsg->len, pmsg->addr, i + 1, num);
 | |
| 		if (pmsg->flags & I2C_M_RD) {
 | |
| 			bool recv_len = pmsg->flags & I2C_M_RECV_LEN;
 | |
| 
 | |
| 			ret = mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i,
 | |
| 				       recv_len);
 | |
| 			if (recv_len && ret > 0)
 | |
| 				pmsg->len = ret;
 | |
| 		} else {
 | |
| 			ret =
 | |
| 			    mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i);
 | |
| 		}
 | |
| 	}
 | |
| 	mpc_i2c_stop(i2c); /* Initiate STOP */
 | |
| 	orig_jiffies = jiffies;
 | |
| 	/* Wait until STOP is seen, allow up to 1 s */
 | |
| 	while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) {
 | |
| 		if (time_after(jiffies, orig_jiffies + HZ)) {
 | |
| 			u8 status = readb(i2c->base + MPC_I2C_SR);
 | |
| 
 | |
| 			dev_dbg(i2c->dev, "timeout\n");
 | |
| 			if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
 | |
| 				writeb(status & ~CSR_MAL,
 | |
| 				       i2c->base + MPC_I2C_SR);
 | |
| 				mpc_i2c_fixup(i2c);
 | |
| 			}
 | |
| 			return -EIO;
 | |
| 		}
 | |
| 		cond_resched();
 | |
| 	}
 | |
| 	return (ret < 0) ? ret : num;
 | |
| }
 | |
| 
 | |
| static u32 mpc_functionality(struct i2c_adapter *adap)
 | |
| {
 | |
| 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
 | |
| 	  | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
 | |
| }
 | |
| 
 | |
| static const struct i2c_algorithm mpc_algo = {
 | |
| 	.master_xfer = mpc_xfer,
 | |
| 	.functionality = mpc_functionality,
 | |
| };
 | |
| 
 | |
| static struct i2c_adapter mpc_ops = {
 | |
| 	.owner = THIS_MODULE,
 | |
| 	.algo = &mpc_algo,
 | |
| 	.timeout = HZ,
 | |
| };
 | |
| 
 | |
| static const struct of_device_id mpc_i2c_of_match[];
 | |
| static int fsl_i2c_probe(struct platform_device *op)
 | |
| {
 | |
| 	const struct of_device_id *match;
 | |
| 	struct mpc_i2c *i2c;
 | |
| 	const u32 *prop;
 | |
| 	u32 clock = MPC_I2C_CLOCK_LEGACY;
 | |
| 	int result = 0;
 | |
| 	int plen;
 | |
| 	struct resource res;
 | |
| 	struct clk *clk;
 | |
| 	int err;
 | |
| 
 | |
| 	match = of_match_device(mpc_i2c_of_match, &op->dev);
 | |
| 	if (!match)
 | |
| 		return -EINVAL;
 | |
| 
 | |
| 	i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
 | |
| 	if (!i2c)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	i2c->dev = &op->dev; /* for debug and error output */
 | |
| 
 | |
| 	init_waitqueue_head(&i2c->queue);
 | |
| 
 | |
| 	i2c->base = of_iomap(op->dev.of_node, 0);
 | |
| 	if (!i2c->base) {
 | |
| 		dev_err(i2c->dev, "failed to map controller\n");
 | |
| 		result = -ENOMEM;
 | |
| 		goto fail_map;
 | |
| 	}
 | |
| 
 | |
| 	i2c->irq = irq_of_parse_and_map(op->dev.of_node, 0);
 | |
| 	if (i2c->irq) { /* no i2c->irq implies polling */
 | |
| 		result = request_irq(i2c->irq, mpc_i2c_isr,
 | |
| 				     IRQF_SHARED, "i2c-mpc", i2c);
 | |
| 		if (result < 0) {
 | |
| 			dev_err(i2c->dev, "failed to attach interrupt\n");
 | |
| 			goto fail_request;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * enable clock for the I2C peripheral (non fatal),
 | |
| 	 * keep a reference upon successful allocation
 | |
| 	 */
 | |
| 	clk = devm_clk_get(&op->dev, NULL);
 | |
| 	if (!IS_ERR(clk)) {
 | |
| 		err = clk_prepare_enable(clk);
 | |
| 		if (err) {
 | |
| 			dev_err(&op->dev, "failed to enable clock\n");
 | |
| 			goto fail_request;
 | |
| 		} else {
 | |
| 			i2c->clk_per = clk;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	if (of_get_property(op->dev.of_node, "fsl,preserve-clocking", NULL)) {
 | |
| 		clock = MPC_I2C_CLOCK_PRESERVE;
 | |
| 	} else {
 | |
| 		prop = of_get_property(op->dev.of_node, "clock-frequency",
 | |
| 					&plen);
 | |
| 		if (prop && plen == sizeof(u32))
 | |
| 			clock = *prop;
 | |
| 	}
 | |
| 
 | |
| 	if (match->data) {
 | |
| 		const struct mpc_i2c_data *data = match->data;
 | |
| 		data->setup(op->dev.of_node, i2c, clock, data->prescaler);
 | |
| 	} else {
 | |
| 		/* Backwards compatibility */
 | |
| 		if (of_get_property(op->dev.of_node, "dfsrr", NULL))
 | |
| 			mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock, 0);
 | |
| 	}
 | |
| 
 | |
| 	prop = of_get_property(op->dev.of_node, "fsl,timeout", &plen);
 | |
| 	if (prop && plen == sizeof(u32)) {
 | |
| 		mpc_ops.timeout = *prop * HZ / 1000000;
 | |
| 		if (mpc_ops.timeout < 5)
 | |
| 			mpc_ops.timeout = 5;
 | |
| 	}
 | |
| 	dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ);
 | |
| 
 | |
| 	platform_set_drvdata(op, i2c);
 | |
| 
 | |
| 	i2c->adap = mpc_ops;
 | |
| 	of_address_to_resource(op->dev.of_node, 0, &res);
 | |
| 	scnprintf(i2c->adap.name, sizeof(i2c->adap.name),
 | |
| 		  "MPC adapter at 0x%llx", (unsigned long long)res.start);
 | |
| 	i2c_set_adapdata(&i2c->adap, i2c);
 | |
| 	i2c->adap.dev.parent = &op->dev;
 | |
| 	i2c->adap.dev.of_node = of_node_get(op->dev.of_node);
 | |
| 
 | |
| 	result = i2c_add_adapter(&i2c->adap);
 | |
| 	if (result < 0) {
 | |
| 		dev_err(i2c->dev, "failed to add adapter\n");
 | |
| 		goto fail_add;
 | |
| 	}
 | |
| 
 | |
| 	return result;
 | |
| 
 | |
|  fail_add:
 | |
| 	if (i2c->clk_per)
 | |
| 		clk_disable_unprepare(i2c->clk_per);
 | |
| 	free_irq(i2c->irq, i2c);
 | |
|  fail_request:
 | |
| 	irq_dispose_mapping(i2c->irq);
 | |
| 	iounmap(i2c->base);
 | |
|  fail_map:
 | |
| 	kfree(i2c);
 | |
| 	return result;
 | |
| };
 | |
| 
 | |
| static int fsl_i2c_remove(struct platform_device *op)
 | |
| {
 | |
| 	struct mpc_i2c *i2c = platform_get_drvdata(op);
 | |
| 
 | |
| 	i2c_del_adapter(&i2c->adap);
 | |
| 
 | |
| 	if (i2c->clk_per)
 | |
| 		clk_disable_unprepare(i2c->clk_per);
 | |
| 
 | |
| 	if (i2c->irq)
 | |
| 		free_irq(i2c->irq, i2c);
 | |
| 
 | |
| 	irq_dispose_mapping(i2c->irq);
 | |
| 	iounmap(i2c->base);
 | |
| 	kfree(i2c);
 | |
| 	return 0;
 | |
| };
 | |
| 
 | |
| #ifdef CONFIG_PM_SLEEP
 | |
| static int mpc_i2c_suspend(struct device *dev)
 | |
| {
 | |
| 	struct mpc_i2c *i2c = dev_get_drvdata(dev);
 | |
| 
 | |
| 	i2c->fdr = readb(i2c->base + MPC_I2C_FDR);
 | |
| 	i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int mpc_i2c_resume(struct device *dev)
 | |
| {
 | |
| 	struct mpc_i2c *i2c = dev_get_drvdata(dev);
 | |
| 
 | |
| 	writeb(i2c->fdr, i2c->base + MPC_I2C_FDR);
 | |
| 	writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume);
 | |
| #define MPC_I2C_PM_OPS	(&mpc_i2c_pm_ops)
 | |
| #else
 | |
| #define MPC_I2C_PM_OPS	NULL
 | |
| #endif
 | |
| 
 | |
| static const struct mpc_i2c_data mpc_i2c_data_512x = {
 | |
| 	.setup = mpc_i2c_setup_512x,
 | |
| };
 | |
| 
 | |
| static const struct mpc_i2c_data mpc_i2c_data_52xx = {
 | |
| 	.setup = mpc_i2c_setup_52xx,
 | |
| };
 | |
| 
 | |
| static const struct mpc_i2c_data mpc_i2c_data_8313 = {
 | |
| 	.setup = mpc_i2c_setup_8xxx,
 | |
| };
 | |
| 
 | |
| static const struct mpc_i2c_data mpc_i2c_data_8543 = {
 | |
| 	.setup = mpc_i2c_setup_8xxx,
 | |
| 	.prescaler = 2,
 | |
| };
 | |
| 
 | |
| static const struct mpc_i2c_data mpc_i2c_data_8544 = {
 | |
| 	.setup = mpc_i2c_setup_8xxx,
 | |
| 	.prescaler = 3,
 | |
| };
 | |
| 
 | |
| static const struct of_device_id mpc_i2c_of_match[] = {
 | |
| 	{.compatible = "mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
 | |
| 	{.compatible = "fsl,mpc5200b-i2c", .data = &mpc_i2c_data_52xx, },
 | |
| 	{.compatible = "fsl,mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
 | |
| 	{.compatible = "fsl,mpc5121-i2c", .data = &mpc_i2c_data_512x, },
 | |
| 	{.compatible = "fsl,mpc8313-i2c", .data = &mpc_i2c_data_8313, },
 | |
| 	{.compatible = "fsl,mpc8543-i2c", .data = &mpc_i2c_data_8543, },
 | |
| 	{.compatible = "fsl,mpc8544-i2c", .data = &mpc_i2c_data_8544, },
 | |
| 	/* Backward compatibility */
 | |
| 	{.compatible = "fsl-i2c", },
 | |
| 	{},
 | |
| };
 | |
| MODULE_DEVICE_TABLE(of, mpc_i2c_of_match);
 | |
| 
 | |
| /* Structure for a device driver */
 | |
| static struct platform_driver mpc_i2c_driver = {
 | |
| 	.probe		= fsl_i2c_probe,
 | |
| 	.remove		= fsl_i2c_remove,
 | |
| 	.driver = {
 | |
| 		.owner = THIS_MODULE,
 | |
| 		.name = DRV_NAME,
 | |
| 		.of_match_table = mpc_i2c_of_match,
 | |
| 		.pm = MPC_I2C_PM_OPS,
 | |
| 	},
 | |
| };
 | |
| 
 | |
| module_platform_driver(mpc_i2c_driver);
 | |
| 
 | |
| MODULE_AUTHOR("Adrian Cox <adrian@humboldt.co.uk>");
 | |
| MODULE_DESCRIPTION("I2C-Bus adapter for MPC107 bridge and "
 | |
| 		   "MPC824x/83xx/85xx/86xx/512x/52xx processors");
 | |
| MODULE_LICENSE("GPL");
 |