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@@ -1,315 +1,554 @@
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/*
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- i2c Support for Atmel's AT91 Two-Wire Interface (TWI)
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-
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- Copyright (C) 2004 Rick Bronson
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- Converted to 2.6 by Andrew Victor <andrew@sanpeople.com>
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-
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- Borrowed heavily from original work by:
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- Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
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-
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- This program is free software; you can redistribute it and/or modify
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- it under the terms of the GNU General Public License as published by
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- the Free Software Foundation; either version 2 of the License, or
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- (at your option) any later version.
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-*/
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+ * i2c Support for Atmel's AT91 Two-Wire Interface (TWI)
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+ *
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+ * Copyright (C) 2011 Weinmann Medical GmbH
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+ * Author: Nikolaus Voss <n.voss@weinmann.de>
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+ *
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+ * Evolved from original work by:
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+ * Copyright (C) 2004 Rick Bronson
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+ * Converted to 2.6 by Andrew Victor <andrew@sanpeople.com>
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+ *
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+ * Borrowed heavily from original work by:
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+ * Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
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+ *
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+ * This program is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU General Public License as published by
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+ * the Free Software Foundation; either version 2 of the License, or
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+ * (at your option) any later version.
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+ */
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-#include <linux/module.h>
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-#include <linux/kernel.h>
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+#include <linux/clk.h>
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+#include <linux/completion.h>
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#include <linux/err.h>
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-#include <linux/slab.h>
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-#include <linux/types.h>
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-#include <linux/delay.h>
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#include <linux/i2c.h>
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-#include <linux/init.h>
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-#include <linux/clk.h>
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-#include <linux/platform_device.h>
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+#include <linux/interrupt.h>
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#include <linux/io.h>
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+#include <linux/module.h>
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+#include <linux/of.h>
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+#include <linux/of_device.h>
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+#include <linux/of_i2c.h>
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+#include <linux/platform_device.h>
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+#include <linux/slab.h>
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+
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+#define TWI_CLK_HZ 100000 /* max 400 Kbits/s */
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+#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */
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+
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+/* AT91 TWI register definitions */
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+#define AT91_TWI_CR 0x0000 /* Control Register */
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+#define AT91_TWI_START 0x0001 /* Send a Start Condition */
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+#define AT91_TWI_STOP 0x0002 /* Send a Stop Condition */
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+#define AT91_TWI_MSEN 0x0004 /* Master Transfer Enable */
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+#define AT91_TWI_SVDIS 0x0020 /* Slave Transfer Disable */
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+#define AT91_TWI_SWRST 0x0080 /* Software Reset */
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+
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+#define AT91_TWI_MMR 0x0004 /* Master Mode Register */
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+#define AT91_TWI_IADRSZ_1 0x0100 /* Internal Device Address Size */
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+#define AT91_TWI_MREAD 0x1000 /* Master Read Direction */
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+
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+#define AT91_TWI_IADR 0x000c /* Internal Address Register */
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+
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+#define AT91_TWI_CWGR 0x0010 /* Clock Waveform Generator Reg */
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+
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+#define AT91_TWI_SR 0x0020 /* Status Register */
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+#define AT91_TWI_TXCOMP 0x0001 /* Transmission Complete */
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+#define AT91_TWI_RXRDY 0x0002 /* Receive Holding Register Ready */
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+#define AT91_TWI_TXRDY 0x0004 /* Transmit Holding Register Ready */
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-#include <mach/at91_twi.h>
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-#include <mach/board.h>
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-#include <mach/cpu.h>
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+#define AT91_TWI_OVRE 0x0040 /* Overrun Error */
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+#define AT91_TWI_UNRE 0x0080 /* Underrun Error */
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+#define AT91_TWI_NACK 0x0100 /* Not Acknowledged */
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-#define TWI_CLOCK 100000 /* Hz. max 400 Kbits/sec */
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+#define AT91_TWI_IER 0x0024 /* Interrupt Enable Register */
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+#define AT91_TWI_IDR 0x0028 /* Interrupt Disable Register */
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+#define AT91_TWI_IMR 0x002c /* Interrupt Mask Register */
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+#define AT91_TWI_RHR 0x0030 /* Receive Holding Register */
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+#define AT91_TWI_THR 0x0034 /* Transmit Holding Register */
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+struct at91_twi_pdata {
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+ unsigned clk_max_div;
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+ unsigned clk_offset;
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+ bool has_unre_flag;
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+};
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+
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+struct at91_twi_dev {
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+ struct device *dev;
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+ void __iomem *base;
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+ struct completion cmd_complete;
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+ struct clk *clk;
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+ u8 *buf;
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+ size_t buf_len;
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+ struct i2c_msg *msg;
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+ int irq;
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+ unsigned transfer_status;
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+ struct i2c_adapter adapter;
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+ unsigned twi_cwgr_reg;
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+ struct at91_twi_pdata *pdata;
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+};
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-static struct clk *twi_clk;
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-static void __iomem *twi_base;
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+static unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg)
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+{
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+ return readl_relaxed(dev->base + reg);
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+}
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+
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+static void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val)
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+{
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+ writel_relaxed(val, dev->base + reg);
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+}
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-#define at91_twi_read(reg) __raw_readl(twi_base + (reg))
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-#define at91_twi_write(reg, val) __raw_writel((val), twi_base + (reg))
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+static void at91_disable_twi_interrupts(struct at91_twi_dev *dev)
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+{
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+ at91_twi_write(dev, AT91_TWI_IDR,
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+ AT91_TWI_TXCOMP | AT91_TWI_RXRDY | AT91_TWI_TXRDY);
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+}
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+static void at91_init_twi_bus(struct at91_twi_dev *dev)
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+{
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+ at91_disable_twi_interrupts(dev);
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+ at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST);
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+ at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_MSEN);
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+ at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SVDIS);
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+ at91_twi_write(dev, AT91_TWI_CWGR, dev->twi_cwgr_reg);
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+}
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/*
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- * Initialize the TWI hardware registers.
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+ * Calculate symmetric clock as stated in datasheet:
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+ * twi_clk = F_MAIN / (2 * (cdiv * (1 << ckdiv) + offset))
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*/
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-static void __devinit at91_twi_hwinit(void)
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+static void __devinit at91_calc_twi_clock(struct at91_twi_dev *dev, int twi_clk)
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{
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- unsigned long cdiv, ckdiv;
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-
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- at91_twi_write(AT91_TWI_IDR, 0xffffffff); /* Disable all interrupts */
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- at91_twi_write(AT91_TWI_CR, AT91_TWI_SWRST); /* Reset peripheral */
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- at91_twi_write(AT91_TWI_CR, AT91_TWI_MSEN); /* Set Master mode */
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-
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- /* Calcuate clock dividers */
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- cdiv = (clk_get_rate(twi_clk) / (2 * TWI_CLOCK)) - 3;
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- cdiv = cdiv + 1; /* round up */
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- ckdiv = 0;
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- while (cdiv > 255) {
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- ckdiv++;
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- cdiv = cdiv >> 1;
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+ int ckdiv, cdiv, div;
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+ struct at91_twi_pdata *pdata = dev->pdata;
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+ int offset = pdata->clk_offset;
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+ int max_ckdiv = pdata->clk_max_div;
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+
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+ div = max(0, (int)DIV_ROUND_UP(clk_get_rate(dev->clk),
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+ 2 * twi_clk) - offset);
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+ ckdiv = fls(div >> 8);
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+ cdiv = div >> ckdiv;
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+
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+ if (ckdiv > max_ckdiv) {
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+ dev_warn(dev->dev, "%d exceeds ckdiv max value which is %d.\n",
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+ ckdiv, max_ckdiv);
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+ ckdiv = max_ckdiv;
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+ cdiv = 255;
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}
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- if (cpu_is_at91rm9200()) { /* AT91RM9200 Errata #22 */
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- if (ckdiv > 5) {
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- printk(KERN_ERR "AT91 I2C: Invalid TWI_CLOCK value!\n");
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- ckdiv = 5;
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- }
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- }
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+ dev->twi_cwgr_reg = (ckdiv << 16) | (cdiv << 8) | cdiv;
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+ dev_dbg(dev->dev, "cdiv %d ckdiv %d\n", cdiv, ckdiv);
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+}
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- at91_twi_write(AT91_TWI_CWGR, (ckdiv << 16) | (cdiv << 8) | cdiv);
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+static void at91_twi_write_next_byte(struct at91_twi_dev *dev)
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+{
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+ if (dev->buf_len <= 0)
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+ return;
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+
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+ at91_twi_write(dev, AT91_TWI_THR, *dev->buf);
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+
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+ /* send stop when last byte has been written */
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+ if (--dev->buf_len == 0)
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+ at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_STOP);
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+
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+ dev_dbg(dev->dev, "wrote 0x%x, to go %d\n", *dev->buf, dev->buf_len);
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+
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+ ++dev->buf;
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}
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-/*
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- * Poll the i2c status register until the specified bit is set.
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- * Returns 0 if timed out (100 msec).
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- */
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-static short at91_poll_status(unsigned long bit)
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+static void at91_twi_read_next_byte(struct at91_twi_dev *dev)
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{
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- int loop_cntr = 10000;
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+ if (dev->buf_len <= 0)
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+ return;
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+
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+ *dev->buf = at91_twi_read(dev, AT91_TWI_RHR) & 0xff;
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+ --dev->buf_len;
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+
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+ /* handle I2C_SMBUS_BLOCK_DATA */
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+ if (unlikely(dev->msg->flags & I2C_M_RECV_LEN)) {
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+ dev->msg->flags &= ~I2C_M_RECV_LEN;
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+ dev->buf_len += *dev->buf;
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+ dev->msg->len = dev->buf_len + 1;
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+ dev_dbg(dev->dev, "received block length %d\n", dev->buf_len);
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+ }
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+
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+ /* send stop if second but last byte has been read */
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+ if (dev->buf_len == 1)
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+ at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_STOP);
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- do {
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- udelay(10);
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- } while (!(at91_twi_read(AT91_TWI_SR) & bit) && (--loop_cntr > 0));
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+ dev_dbg(dev->dev, "read 0x%x, to go %d\n", *dev->buf, dev->buf_len);
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- return (loop_cntr > 0);
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+ ++dev->buf;
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}
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-static int xfer_read(struct i2c_adapter *adap, unsigned char *buf, int length)
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+static irqreturn_t atmel_twi_interrupt(int irq, void *dev_id)
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{
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- /* Send Start */
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- at91_twi_write(AT91_TWI_CR, AT91_TWI_START);
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-
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- /* Read data */
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- while (length--) {
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- if (!length) /* need to send Stop before reading last byte */
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- at91_twi_write(AT91_TWI_CR, AT91_TWI_STOP);
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- if (!at91_poll_status(AT91_TWI_RXRDY)) {
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- dev_dbg(&adap->dev, "RXRDY timeout\n");
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- return -ETIMEDOUT;
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- }
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- *buf++ = (at91_twi_read(AT91_TWI_RHR) & 0xff);
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+ struct at91_twi_dev *dev = dev_id;
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+ const unsigned status = at91_twi_read(dev, AT91_TWI_SR);
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+ const unsigned irqstatus = status & at91_twi_read(dev, AT91_TWI_IMR);
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+
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+ if (!irqstatus)
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+ return IRQ_NONE;
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+ else if (irqstatus & AT91_TWI_RXRDY)
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+ at91_twi_read_next_byte(dev);
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+ else if (irqstatus & AT91_TWI_TXRDY)
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+ at91_twi_write_next_byte(dev);
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+
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+ /* catch error flags */
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+ dev->transfer_status |= status;
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+
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+ if (irqstatus & AT91_TWI_TXCOMP) {
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+ at91_disable_twi_interrupts(dev);
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+ complete(&dev->cmd_complete);
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}
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- return 0;
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+ return IRQ_HANDLED;
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}
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-static int xfer_write(struct i2c_adapter *adap, unsigned char *buf, int length)
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+static int at91_do_twi_transfer(struct at91_twi_dev *dev)
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{
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- /* Load first byte into transmitter */
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- at91_twi_write(AT91_TWI_THR, *buf++);
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+ int ret;
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+ bool has_unre_flag = dev->pdata->has_unre_flag;
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- /* Send Start */
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- at91_twi_write(AT91_TWI_CR, AT91_TWI_START);
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+ dev_dbg(dev->dev, "transfer: %s %d bytes.\n",
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+ (dev->msg->flags & I2C_M_RD) ? "read" : "write", dev->buf_len);
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- do {
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- if (!at91_poll_status(AT91_TWI_TXRDY)) {
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- dev_dbg(&adap->dev, "TXRDY timeout\n");
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- return -ETIMEDOUT;
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- }
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+ INIT_COMPLETION(dev->cmd_complete);
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+ dev->transfer_status = 0;
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+ if (dev->msg->flags & I2C_M_RD) {
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+ unsigned start_flags = AT91_TWI_START;
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- length--; /* byte was transmitted */
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+ if (at91_twi_read(dev, AT91_TWI_SR) & AT91_TWI_RXRDY) {
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+ dev_err(dev->dev, "RXRDY still set!");
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+ at91_twi_read(dev, AT91_TWI_RHR);
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+ }
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- if (length > 0) /* more data to send? */
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- at91_twi_write(AT91_TWI_THR, *buf++);
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- } while (length);
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+ /* if only one byte is to be read, immediately stop transfer */
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+ if (dev->buf_len <= 1 && !(dev->msg->flags & I2C_M_RECV_LEN))
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+ start_flags |= AT91_TWI_STOP;
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+ at91_twi_write(dev, AT91_TWI_CR, start_flags);
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+ at91_twi_write(dev, AT91_TWI_IER,
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+ AT91_TWI_TXCOMP | AT91_TWI_RXRDY);
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+ } else {
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+ at91_twi_write_next_byte(dev);
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+ at91_twi_write(dev, AT91_TWI_IER,
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+ AT91_TWI_TXCOMP | AT91_TWI_TXRDY);
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+ }
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- /* Send Stop */
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- at91_twi_write(AT91_TWI_CR, AT91_TWI_STOP);
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+ ret = wait_for_completion_interruptible_timeout(&dev->cmd_complete,
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+ dev->adapter.timeout);
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+ if (ret == 0) {
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+ dev_err(dev->dev, "controller timed out\n");
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+ at91_init_twi_bus(dev);
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+ return -ETIMEDOUT;
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+ }
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+ if (dev->transfer_status & AT91_TWI_NACK) {
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+ dev_dbg(dev->dev, "received nack\n");
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+ return -EREMOTEIO;
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+ }
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+ if (dev->transfer_status & AT91_TWI_OVRE) {
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+ dev_err(dev->dev, "overrun while reading\n");
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+ return -EIO;
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+ }
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+ if (has_unre_flag && dev->transfer_status & AT91_TWI_UNRE) {
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+ dev_err(dev->dev, "underrun while writing\n");
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+ return -EIO;
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+ }
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+ dev_dbg(dev->dev, "transfer complete\n");
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return 0;
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}
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-/*
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- * Generic i2c master transfer entrypoint.
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- *
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- * Note: We do not use Atmel's feature of storing the "internal device address".
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- * Instead the "internal device address" has to be written using a separate
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- * i2c message.
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- * http://lists.arm.linux.org.uk/pipermail/linux-arm-kernel/2004-September/024411.html
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- */
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-static int at91_xfer(struct i2c_adapter *adap, struct i2c_msg *pmsg, int num)
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|
+static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
|
|
|
{
|
|
|
- int i, ret;
|
|
|
+ struct at91_twi_dev *dev = i2c_get_adapdata(adap);
|
|
|
+ int ret;
|
|
|
+ unsigned int_addr_flag = 0;
|
|
|
+ struct i2c_msg *m_start = msg;
|
|
|
|
|
|
dev_dbg(&adap->dev, "at91_xfer: processing %d messages:\n", num);
|
|
|
|
|
|
- for (i = 0; i < num; i++) {
|
|
|
- dev_dbg(&adap->dev, " #%d: %sing %d byte%s %s 0x%02x\n", i,
|
|
|
- pmsg->flags & I2C_M_RD ? "read" : "writ",
|
|
|
- pmsg->len, pmsg->len > 1 ? "s" : "",
|
|
|
- pmsg->flags & I2C_M_RD ? "from" : "to", pmsg->addr);
|
|
|
-
|
|
|
- at91_twi_write(AT91_TWI_MMR, (pmsg->addr << 16)
|
|
|
- | ((pmsg->flags & I2C_M_RD) ? AT91_TWI_MREAD : 0));
|
|
|
-
|
|
|
- if (pmsg->len && pmsg->buf) { /* sanity check */
|
|
|
- if (pmsg->flags & I2C_M_RD)
|
|
|
- ret = xfer_read(adap, pmsg->buf, pmsg->len);
|
|
|
- else
|
|
|
- ret = xfer_write(adap, pmsg->buf, pmsg->len);
|
|
|
-
|
|
|
- if (ret)
|
|
|
- return ret;
|
|
|
-
|
|
|
- /* Wait until transfer is finished */
|
|
|
- if (!at91_poll_status(AT91_TWI_TXCOMP)) {
|
|
|
- dev_dbg(&adap->dev, "TXCOMP timeout\n");
|
|
|
- return -ETIMEDOUT;
|
|
|
- }
|
|
|
+ /*
|
|
|
+ * The hardware can handle at most two messages concatenated by a
|
|
|
+ * repeated start via it's internal address feature.
|
|
|
+ */
|
|
|
+ if (num > 2) {
|
|
|
+ dev_err(dev->dev,
|
|
|
+ "cannot handle more than two concatenated messages.\n");
|
|
|
+ return 0;
|
|
|
+ } else if (num == 2) {
|
|
|
+ int internal_address = 0;
|
|
|
+ int i;
|
|
|
+
|
|
|
+ if (msg->flags & I2C_M_RD) {
|
|
|
+ dev_err(dev->dev, "first transfer must be write.\n");
|
|
|
+ return -EINVAL;
|
|
|
}
|
|
|
- dev_dbg(&adap->dev, "transfer complete\n");
|
|
|
- pmsg++; /* next message */
|
|
|
+ if (msg->len > 3) {
|
|
|
+ dev_err(dev->dev, "first message size must be <= 3.\n");
|
|
|
+ return -EINVAL;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* 1st msg is put into the internal address, start with 2nd */
|
|
|
+ m_start = &msg[1];
|
|
|
+ for (i = 0; i < msg->len; ++i) {
|
|
|
+ const unsigned addr = msg->buf[msg->len - 1 - i];
|
|
|
+
|
|
|
+ internal_address |= addr << (8 * i);
|
|
|
+ int_addr_flag += AT91_TWI_IADRSZ_1;
|
|
|
+ }
|
|
|
+ at91_twi_write(dev, AT91_TWI_IADR, internal_address);
|
|
|
}
|
|
|
- return i;
|
|
|
+
|
|
|
+ at91_twi_write(dev, AT91_TWI_MMR, (m_start->addr << 16) | int_addr_flag
|
|
|
+ | ((m_start->flags & I2C_M_RD) ? AT91_TWI_MREAD : 0));
|
|
|
+
|
|
|
+ dev->buf_len = m_start->len;
|
|
|
+ dev->buf = m_start->buf;
|
|
|
+ dev->msg = m_start;
|
|
|
+
|
|
|
+ ret = at91_do_twi_transfer(dev);
|
|
|
+
|
|
|
+ return (ret < 0) ? ret : num;
|
|
|
}
|
|
|
|
|
|
-/*
|
|
|
- * Return list of supported functionality.
|
|
|
- */
|
|
|
-static u32 at91_func(struct i2c_adapter *adapter)
|
|
|
+static u32 at91_twi_func(struct i2c_adapter *adapter)
|
|
|
{
|
|
|
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
|
|
|
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
|
|
|
+ | I2C_FUNC_SMBUS_READ_BLOCK_DATA;
|
|
|
}
|
|
|
|
|
|
-static struct i2c_algorithm at91_algorithm = {
|
|
|
- .master_xfer = at91_xfer,
|
|
|
- .functionality = at91_func,
|
|
|
+static struct i2c_algorithm at91_twi_algorithm = {
|
|
|
+ .master_xfer = at91_twi_xfer,
|
|
|
+ .functionality = at91_twi_func,
|
|
|
};
|
|
|
|
|
|
-/*
|
|
|
- * Main initialization routine.
|
|
|
- */
|
|
|
-static int __devinit at91_i2c_probe(struct platform_device *pdev)
|
|
|
-{
|
|
|
- struct i2c_adapter *adapter;
|
|
|
- struct resource *res;
|
|
|
- int rc;
|
|
|
+static struct at91_twi_pdata at91rm9200_config = {
|
|
|
+ .clk_max_div = 5,
|
|
|
+ .clk_offset = 3,
|
|
|
+ .has_unre_flag = true,
|
|
|
+};
|
|
|
|
|
|
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
|
- if (!res)
|
|
|
- return -ENXIO;
|
|
|
+static struct at91_twi_pdata at91sam9261_config = {
|
|
|
+ .clk_max_div = 5,
|
|
|
+ .clk_offset = 4,
|
|
|
+ .has_unre_flag = false,
|
|
|
+};
|
|
|
|
|
|
- if (!request_mem_region(res->start, resource_size(res), "at91_i2c"))
|
|
|
- return -EBUSY;
|
|
|
+static struct at91_twi_pdata at91sam9260_config = {
|
|
|
+ .clk_max_div = 7,
|
|
|
+ .clk_offset = 4,
|
|
|
+ .has_unre_flag = false,
|
|
|
+};
|
|
|
+
|
|
|
+static struct at91_twi_pdata at91sam9g20_config = {
|
|
|
+ .clk_max_div = 7,
|
|
|
+ .clk_offset = 4,
|
|
|
+ .has_unre_flag = false,
|
|
|
+};
|
|
|
+
|
|
|
+static struct at91_twi_pdata at91sam9g10_config = {
|
|
|
+ .clk_max_div = 7,
|
|
|
+ .clk_offset = 4,
|
|
|
+ .has_unre_flag = false,
|
|
|
+};
|
|
|
|
|
|
- twi_base = ioremap(res->start, resource_size(res));
|
|
|
- if (!twi_base) {
|
|
|
- rc = -ENOMEM;
|
|
|
- goto fail0;
|
|
|
+static struct at91_twi_pdata at91sam9x5_config = {
|
|
|
+ .clk_max_div = 7,
|
|
|
+ .clk_offset = 4,
|
|
|
+ .has_unre_flag = false,
|
|
|
+};
|
|
|
+
|
|
|
+static const struct platform_device_id at91_twi_devtypes[] = {
|
|
|
+ {
|
|
|
+ .name = "i2c-at91rm9200",
|
|
|
+ .driver_data = (unsigned long) &at91rm9200_config,
|
|
|
+ }, {
|
|
|
+ .name = "i2c-at91sam9261",
|
|
|
+ .driver_data = (unsigned long) &at91sam9261_config,
|
|
|
+ }, {
|
|
|
+ .name = "i2c-at91sam9260",
|
|
|
+ .driver_data = (unsigned long) &at91sam9260_config,
|
|
|
+ }, {
|
|
|
+ .name = "i2c-at91sam9g20",
|
|
|
+ .driver_data = (unsigned long) &at91sam9g20_config,
|
|
|
+ }, {
|
|
|
+ .name = "i2c-at91sam9g10",
|
|
|
+ .driver_data = (unsigned long) &at91sam9g10_config,
|
|
|
+ }, {
|
|
|
+ /* sentinel */
|
|
|
}
|
|
|
+};
|
|
|
|
|
|
- twi_clk = clk_get(NULL, "twi_clk");
|
|
|
- if (IS_ERR(twi_clk)) {
|
|
|
- dev_err(&pdev->dev, "no clock defined\n");
|
|
|
- rc = -ENODEV;
|
|
|
- goto fail1;
|
|
|
+#if defined(CONFIG_OF)
|
|
|
+static const struct of_device_id atmel_twi_dt_ids[] = {
|
|
|
+ {
|
|
|
+ .compatible = "atmel,at91sam9260-i2c",
|
|
|
+ .data = &at91sam9260_config,
|
|
|
+ } , {
|
|
|
+ .compatible = "atmel,at91sam9g20-i2c",
|
|
|
+ .data = &at91sam9g20_config,
|
|
|
+ } , {
|
|
|
+ .compatible = "atmel,at91sam9g10-i2c",
|
|
|
+ .data = &at91sam9g10_config,
|
|
|
+ }, {
|
|
|
+ .compatible = "atmel,at91sam9x5-i2c",
|
|
|
+ .data = &at91sam9x5_config,
|
|
|
+ }, {
|
|
|
+ /* sentinel */
|
|
|
}
|
|
|
+};
|
|
|
+MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
|
|
|
+#else
|
|
|
+#define atmel_twi_dt_ids NULL
|
|
|
+#endif
|
|
|
|
|
|
- adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL);
|
|
|
- if (adapter == NULL) {
|
|
|
- dev_err(&pdev->dev, "can't allocate inteface!\n");
|
|
|
- rc = -ENOMEM;
|
|
|
- goto fail2;
|
|
|
+static struct at91_twi_pdata * __devinit at91_twi_get_driver_data(
|
|
|
+ struct platform_device *pdev)
|
|
|
+{
|
|
|
+ if (pdev->dev.of_node) {
|
|
|
+ const struct of_device_id *match;
|
|
|
+ match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node);
|
|
|
+ if (!match)
|
|
|
+ return NULL;
|
|
|
+ return match->data;
|
|
|
}
|
|
|
- snprintf(adapter->name, sizeof(adapter->name), "AT91");
|
|
|
- adapter->algo = &at91_algorithm;
|
|
|
- adapter->class = I2C_CLASS_HWMON;
|
|
|
- adapter->dev.parent = &pdev->dev;
|
|
|
- /* adapter->id == 0 ... only one TWI controller for now */
|
|
|
+ return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data;
|
|
|
+}
|
|
|
+
|
|
|
+static int __devinit at91_twi_probe(struct platform_device *pdev)
|
|
|
+{
|
|
|
+ struct at91_twi_dev *dev;
|
|
|
+ struct resource *mem;
|
|
|
+ int rc;
|
|
|
+
|
|
|
+ dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
|
|
|
+ if (!dev)
|
|
|
+ return -ENOMEM;
|
|
|
+ init_completion(&dev->cmd_complete);
|
|
|
+ dev->dev = &pdev->dev;
|
|
|
+
|
|
|
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
|
+ if (!mem)
|
|
|
+ return -ENODEV;
|
|
|
+
|
|
|
+ dev->pdata = at91_twi_get_driver_data(pdev);
|
|
|
+ if (!dev->pdata)
|
|
|
+ return -ENODEV;
|
|
|
|
|
|
- platform_set_drvdata(pdev, adapter);
|
|
|
+ dev->base = devm_request_and_ioremap(&pdev->dev, mem);
|
|
|
+ if (!dev->base)
|
|
|
+ return -EBUSY;
|
|
|
|
|
|
- clk_enable(twi_clk); /* enable peripheral clock */
|
|
|
- at91_twi_hwinit(); /* initialize TWI controller */
|
|
|
+ dev->irq = platform_get_irq(pdev, 0);
|
|
|
+ if (dev->irq < 0)
|
|
|
+ return dev->irq;
|
|
|
|
|
|
- rc = i2c_add_numbered_adapter(adapter);
|
|
|
+ rc = devm_request_irq(&pdev->dev, dev->irq, atmel_twi_interrupt, 0,
|
|
|
+ dev_name(dev->dev), dev);
|
|
|
if (rc) {
|
|
|
- dev_err(&pdev->dev, "Adapter %s registration failed\n",
|
|
|
- adapter->name);
|
|
|
- goto fail3;
|
|
|
+ dev_err(dev->dev, "Cannot get irq %d: %d\n", dev->irq, rc);
|
|
|
+ return rc;
|
|
|
}
|
|
|
|
|
|
- dev_info(&pdev->dev, "AT91 i2c bus driver.\n");
|
|
|
- return 0;
|
|
|
+ platform_set_drvdata(pdev, dev);
|
|
|
|
|
|
-fail3:
|
|
|
- platform_set_drvdata(pdev, NULL);
|
|
|
- kfree(adapter);
|
|
|
- clk_disable(twi_clk);
|
|
|
-fail2:
|
|
|
- clk_put(twi_clk);
|
|
|
-fail1:
|
|
|
- iounmap(twi_base);
|
|
|
-fail0:
|
|
|
- release_mem_region(res->start, resource_size(res));
|
|
|
+ dev->clk = devm_clk_get(dev->dev, NULL);
|
|
|
+ if (IS_ERR(dev->clk)) {
|
|
|
+ dev_err(dev->dev, "no clock defined\n");
|
|
|
+ return -ENODEV;
|
|
|
+ }
|
|
|
+ clk_prepare_enable(dev->clk);
|
|
|
+
|
|
|
+ at91_calc_twi_clock(dev, TWI_CLK_HZ);
|
|
|
+ at91_init_twi_bus(dev);
|
|
|
+
|
|
|
+ snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91");
|
|
|
+ i2c_set_adapdata(&dev->adapter, dev);
|
|
|
+ dev->adapter.owner = THIS_MODULE;
|
|
|
+ dev->adapter.class = I2C_CLASS_HWMON;
|
|
|
+ dev->adapter.algo = &at91_twi_algorithm;
|
|
|
+ dev->adapter.dev.parent = dev->dev;
|
|
|
+ dev->adapter.nr = pdev->id;
|
|
|
+ dev->adapter.timeout = AT91_I2C_TIMEOUT;
|
|
|
+ dev->adapter.dev.of_node = pdev->dev.of_node;
|
|
|
+
|
|
|
+ rc = i2c_add_numbered_adapter(&dev->adapter);
|
|
|
+ if (rc) {
|
|
|
+ dev_err(dev->dev, "Adapter %s registration failed\n",
|
|
|
+ dev->adapter.name);
|
|
|
+ clk_disable_unprepare(dev->clk);
|
|
|
+ return rc;
|
|
|
+ }
|
|
|
|
|
|
- return rc;
|
|
|
+ of_i2c_register_devices(&dev->adapter);
|
|
|
+
|
|
|
+ dev_info(dev->dev, "AT91 i2c bus driver.\n");
|
|
|
+ return 0;
|
|
|
}
|
|
|
|
|
|
-static int __devexit at91_i2c_remove(struct platform_device *pdev)
|
|
|
+static int __devexit at91_twi_remove(struct platform_device *pdev)
|
|
|
{
|
|
|
- struct i2c_adapter *adapter = platform_get_drvdata(pdev);
|
|
|
- struct resource *res;
|
|
|
+ struct at91_twi_dev *dev = platform_get_drvdata(pdev);
|
|
|
int rc;
|
|
|
|
|
|
- rc = i2c_del_adapter(adapter);
|
|
|
- platform_set_drvdata(pdev, NULL);
|
|
|
-
|
|
|
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
|
- iounmap(twi_base);
|
|
|
- release_mem_region(res->start, resource_size(res));
|
|
|
-
|
|
|
- clk_disable(twi_clk); /* disable peripheral clock */
|
|
|
- clk_put(twi_clk);
|
|
|
+ rc = i2c_del_adapter(&dev->adapter);
|
|
|
+ clk_disable_unprepare(dev->clk);
|
|
|
|
|
|
return rc;
|
|
|
}
|
|
|
|
|
|
#ifdef CONFIG_PM
|
|
|
|
|
|
-/* NOTE: could save a few mA by keeping clock off outside of at91_xfer... */
|
|
|
-
|
|
|
-static int at91_i2c_suspend(struct device *dev)
|
|
|
+static int at91_twi_runtime_suspend(struct device *dev)
|
|
|
{
|
|
|
- clk_disable(twi_clk);
|
|
|
+ struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
|
|
|
+
|
|
|
+ clk_disable(twi_dev->clk);
|
|
|
+
|
|
|
return 0;
|
|
|
}
|
|
|
|
|
|
-static int at91_i2c_resume(struct device *dev)
|
|
|
+static int at91_twi_runtime_resume(struct device *dev)
|
|
|
{
|
|
|
- return clk_enable(twi_clk);
|
|
|
+ struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
|
|
|
+
|
|
|
+ return clk_enable(twi_dev->clk);
|
|
|
}
|
|
|
|
|
|
-static SIMPLE_DEV_PM_OPS(at91_i2c_pm, at91_i2c_suspend, at91_i2c_resume);
|
|
|
-#define AT91_I2C_PM (&at91_i2c_pm)
|
|
|
+static const struct dev_pm_ops at91_twi_pm = {
|
|
|
+ .runtime_suspend = at91_twi_runtime_suspend,
|
|
|
+ .runtime_resume = at91_twi_runtime_resume,
|
|
|
+};
|
|
|
|
|
|
+#define at91_twi_pm_ops (&at91_twi_pm)
|
|
|
#else
|
|
|
-#define AT91_I2C_PM NULL
|
|
|
+#define at91_twi_pm_ops NULL
|
|
|
#endif
|
|
|
|
|
|
-static struct platform_driver at91_i2c_driver = {
|
|
|
- .probe = at91_i2c_probe,
|
|
|
- .remove = __devexit_p(at91_i2c_remove),
|
|
|
+static struct platform_driver at91_twi_driver = {
|
|
|
+ .probe = at91_twi_probe,
|
|
|
+ .remove = __devexit_p(at91_twi_remove),
|
|
|
+ .id_table = at91_twi_devtypes,
|
|
|
.driver = {
|
|
|
.name = "at91_i2c",
|
|
|
.owner = THIS_MODULE,
|
|
|
- .pm = AT91_I2C_PM,
|
|
|
+ .of_match_table = atmel_twi_dt_ids,
|
|
|
+ .pm = at91_twi_pm_ops,
|
|
|
},
|
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};
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-module_platform_driver(at91_i2c_driver);
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|
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+static int __init at91_twi_init(void)
|
|
|
+{
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|
|
+ return platform_driver_register(&at91_twi_driver);
|
|
|
+}
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+
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|
+static void __exit at91_twi_exit(void)
|
|
|
+{
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|
|
+ platform_driver_unregister(&at91_twi_driver);
|
|
|
+}
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+
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|
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+subsys_initcall(at91_twi_init);
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|
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+module_exit(at91_twi_exit);
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|
|
|
|
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-MODULE_AUTHOR("Rick Bronson");
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|
|
+MODULE_AUTHOR("Nikolaus Voss <n.voss@weinmann.de>");
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|
|
MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91");
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|
|
MODULE_LICENSE("GPL");
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|
|
MODULE_ALIAS("platform:at91_i2c");
|