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631 lines
16 KiB
631 lines
16 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* BCM2835 master mode driver |
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*/ |
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|
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#include <linux/clk.h> |
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#include <linux/clkdev.h> |
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#include <linux/clk-provider.h> |
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#include <linux/completion.h> |
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#include <linux/err.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/module.h> |
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#include <linux/of_device.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 BCM2835_I2C_C 0x0 |
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#define BCM2835_I2C_S 0x4 |
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#define BCM2835_I2C_DLEN 0x8 |
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#define BCM2835_I2C_A 0xc |
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#define BCM2835_I2C_FIFO 0x10 |
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#define BCM2835_I2C_DIV 0x14 |
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#define BCM2835_I2C_DEL 0x18 |
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#define BCM2835_I2C_CLKT 0x1c |
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|
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#define BCM2835_I2C_C_READ BIT(0) |
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#define BCM2835_I2C_C_CLEAR BIT(4) /* bits 4 and 5 both clear */ |
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#define BCM2835_I2C_C_ST BIT(7) |
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#define BCM2835_I2C_C_INTD BIT(8) |
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#define BCM2835_I2C_C_INTT BIT(9) |
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#define BCM2835_I2C_C_INTR BIT(10) |
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#define BCM2835_I2C_C_I2CEN BIT(15) |
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|
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#define BCM2835_I2C_S_TA BIT(0) |
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#define BCM2835_I2C_S_DONE BIT(1) |
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#define BCM2835_I2C_S_TXW BIT(2) |
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#define BCM2835_I2C_S_RXR BIT(3) |
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#define BCM2835_I2C_S_TXD BIT(4) |
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#define BCM2835_I2C_S_RXD BIT(5) |
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#define BCM2835_I2C_S_TXE BIT(6) |
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#define BCM2835_I2C_S_RXF BIT(7) |
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#define BCM2835_I2C_S_ERR BIT(8) |
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#define BCM2835_I2C_S_CLKT BIT(9) |
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#define BCM2835_I2C_S_LEN BIT(10) /* Fake bit for SW error reporting */ |
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#define BCM2835_I2C_FEDL_SHIFT 16 |
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#define BCM2835_I2C_REDL_SHIFT 0 |
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|
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#define BCM2835_I2C_CDIV_MIN 0x0002 |
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#define BCM2835_I2C_CDIV_MAX 0xFFFE |
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|
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static unsigned int debug; |
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module_param(debug, uint, 0644); |
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MODULE_PARM_DESC(debug, "1=err, 2=isr, 3=xfer"); |
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|
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#define BCM2835_DEBUG_MAX 512 |
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struct bcm2835_debug { |
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struct i2c_msg *msg; |
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int msg_idx; |
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size_t remain; |
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u32 status; |
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}; |
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struct bcm2835_i2c_dev { |
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struct device *dev; |
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void __iomem *regs; |
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int irq; |
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struct i2c_adapter adapter; |
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struct completion completion; |
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struct i2c_msg *curr_msg; |
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struct clk *bus_clk; |
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int num_msgs; |
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u32 msg_err; |
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u8 *msg_buf; |
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size_t msg_buf_remaining; |
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struct bcm2835_debug debug[BCM2835_DEBUG_MAX]; |
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unsigned int debug_num; |
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unsigned int debug_num_msgs; |
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}; |
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static inline void bcm2835_debug_add(struct bcm2835_i2c_dev *i2c_dev, u32 s) |
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{ |
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if (!i2c_dev->debug_num_msgs || i2c_dev->debug_num >= BCM2835_DEBUG_MAX) |
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return; |
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|
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i2c_dev->debug[i2c_dev->debug_num].msg = i2c_dev->curr_msg; |
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i2c_dev->debug[i2c_dev->debug_num].msg_idx = |
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i2c_dev->debug_num_msgs - i2c_dev->num_msgs; |
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i2c_dev->debug[i2c_dev->debug_num].remain = i2c_dev->msg_buf_remaining; |
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i2c_dev->debug[i2c_dev->debug_num].status = s; |
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i2c_dev->debug_num++; |
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} |
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static void bcm2835_debug_print_status(struct bcm2835_i2c_dev *i2c_dev, |
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struct bcm2835_debug *d) |
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{ |
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u32 s = d->status; |
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|
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pr_info("isr: remain=%zu, status=0x%x : %s%s%s%s%s%s%s%s%s%s [i2c%d]\n", |
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d->remain, s, |
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s & BCM2835_I2C_S_TA ? "TA " : "", |
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s & BCM2835_I2C_S_DONE ? "DONE " : "", |
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s & BCM2835_I2C_S_TXW ? "TXW " : "", |
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s & BCM2835_I2C_S_RXR ? "RXR " : "", |
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s & BCM2835_I2C_S_TXD ? "TXD " : "", |
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s & BCM2835_I2C_S_RXD ? "RXD " : "", |
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s & BCM2835_I2C_S_TXE ? "TXE " : "", |
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s & BCM2835_I2C_S_RXF ? "RXF " : "", |
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s & BCM2835_I2C_S_ERR ? "ERR " : "", |
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s & BCM2835_I2C_S_CLKT ? "CLKT " : "", |
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i2c_dev->adapter.nr); |
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} |
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|
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static void bcm2835_debug_print_msg(struct bcm2835_i2c_dev *i2c_dev, |
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struct i2c_msg *msg, int i, int total, |
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const char *fname) |
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{ |
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pr_info("%s: msg(%d/%d) %s addr=0x%02x, len=%u flags=%s%s%s%s%s%s%s [i2c%d]\n", |
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fname, i, total, |
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msg->flags & I2C_M_RD ? "read" : "write", msg->addr, msg->len, |
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msg->flags & I2C_M_TEN ? "TEN" : "", |
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msg->flags & I2C_M_RECV_LEN ? "RECV_LEN" : "", |
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msg->flags & I2C_M_NO_RD_ACK ? "NO_RD_ACK" : "", |
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msg->flags & I2C_M_IGNORE_NAK ? "IGNORE_NAK" : "", |
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msg->flags & I2C_M_REV_DIR_ADDR ? "REV_DIR_ADDR" : "", |
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msg->flags & I2C_M_NOSTART ? "NOSTART" : "", |
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msg->flags & I2C_M_STOP ? "STOP" : "", |
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i2c_dev->adapter.nr); |
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} |
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|
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static void bcm2835_debug_print(struct bcm2835_i2c_dev *i2c_dev) |
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{ |
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struct bcm2835_debug *d; |
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unsigned int i; |
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|
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for (i = 0; i < i2c_dev->debug_num; i++) { |
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d = &i2c_dev->debug[i]; |
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if (d->status == ~0) |
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bcm2835_debug_print_msg(i2c_dev, d->msg, d->msg_idx, |
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i2c_dev->debug_num_msgs, "start_transfer"); |
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else |
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bcm2835_debug_print_status(i2c_dev, d); |
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} |
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if (i2c_dev->debug_num >= BCM2835_DEBUG_MAX) |
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pr_info("BCM2835_DEBUG_MAX reached\n"); |
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} |
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static inline void bcm2835_i2c_writel(struct bcm2835_i2c_dev *i2c_dev, |
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u32 reg, u32 val) |
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{ |
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writel(val, i2c_dev->regs + reg); |
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} |
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static inline u32 bcm2835_i2c_readl(struct bcm2835_i2c_dev *i2c_dev, u32 reg) |
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{ |
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return readl(i2c_dev->regs + reg); |
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} |
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#define to_clk_bcm2835_i2c(_hw) container_of(_hw, struct clk_bcm2835_i2c, hw) |
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struct clk_bcm2835_i2c { |
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struct clk_hw hw; |
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struct bcm2835_i2c_dev *i2c_dev; |
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}; |
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static int clk_bcm2835_i2c_calc_divider(unsigned long rate, |
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unsigned long parent_rate) |
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{ |
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u32 divider = DIV_ROUND_UP(parent_rate, rate); |
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|
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/* |
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* Per the datasheet, the register is always interpreted as an even |
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* number, by rounding down. In other words, the LSB is ignored. So, |
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* if the LSB is set, increment the divider to avoid any issue. |
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*/ |
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if (divider & 1) |
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divider++; |
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if ((divider < BCM2835_I2C_CDIV_MIN) || |
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(divider > BCM2835_I2C_CDIV_MAX)) |
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return -EINVAL; |
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|
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return divider; |
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} |
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static int clk_bcm2835_i2c_set_rate(struct clk_hw *hw, unsigned long rate, |
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unsigned long parent_rate) |
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{ |
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struct clk_bcm2835_i2c *div = to_clk_bcm2835_i2c(hw); |
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u32 redl, fedl; |
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u32 clk_tout; |
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u32 divider = clk_bcm2835_i2c_calc_divider(rate, parent_rate); |
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|
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if (divider == -EINVAL) |
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return -EINVAL; |
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bcm2835_i2c_writel(div->i2c_dev, BCM2835_I2C_DIV, divider); |
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|
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/* |
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* Number of core clocks to wait after falling edge before |
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* outputting the next data bit. Note that both FEDL and REDL |
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* can't be greater than CDIV/2. |
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*/ |
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fedl = max(divider / 16, 1u); |
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|
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/* |
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* Number of core clocks to wait after rising edge before |
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* sampling the next incoming data bit. |
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*/ |
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redl = max(divider / 4, 1u); |
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|
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bcm2835_i2c_writel(div->i2c_dev, BCM2835_I2C_DEL, |
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(fedl << BCM2835_I2C_FEDL_SHIFT) | |
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(redl << BCM2835_I2C_REDL_SHIFT)); |
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|
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/* |
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* Set the clock stretch timeout to the SMBUs-recommended 35ms. |
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*/ |
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if (rate > 0xffff*1000/35) |
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clk_tout = 0xffff; |
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else |
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clk_tout = 35*rate/1000; |
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bcm2835_i2c_writel(div->i2c_dev, BCM2835_I2C_CLKT, clk_tout); |
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return 0; |
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} |
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static long clk_bcm2835_i2c_round_rate(struct clk_hw *hw, unsigned long rate, |
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unsigned long *parent_rate) |
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{ |
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u32 divider = clk_bcm2835_i2c_calc_divider(rate, *parent_rate); |
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|
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return DIV_ROUND_UP(*parent_rate, divider); |
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} |
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static unsigned long clk_bcm2835_i2c_recalc_rate(struct clk_hw *hw, |
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unsigned long parent_rate) |
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{ |
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struct clk_bcm2835_i2c *div = to_clk_bcm2835_i2c(hw); |
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u32 divider = bcm2835_i2c_readl(div->i2c_dev, BCM2835_I2C_DIV); |
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return DIV_ROUND_UP(parent_rate, divider); |
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} |
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static const struct clk_ops clk_bcm2835_i2c_ops = { |
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.set_rate = clk_bcm2835_i2c_set_rate, |
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.round_rate = clk_bcm2835_i2c_round_rate, |
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.recalc_rate = clk_bcm2835_i2c_recalc_rate, |
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}; |
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static struct clk *bcm2835_i2c_register_div(struct device *dev, |
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struct clk *mclk, |
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struct bcm2835_i2c_dev *i2c_dev) |
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{ |
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struct clk_init_data init; |
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struct clk_bcm2835_i2c *priv; |
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char name[32]; |
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const char *mclk_name; |
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|
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snprintf(name, sizeof(name), "%s_div", dev_name(dev)); |
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mclk_name = __clk_get_name(mclk); |
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init.ops = &clk_bcm2835_i2c_ops; |
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init.name = name; |
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init.parent_names = (const char* []) { mclk_name }; |
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init.num_parents = 1; |
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init.flags = 0; |
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priv = devm_kzalloc(dev, sizeof(struct clk_bcm2835_i2c), GFP_KERNEL); |
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if (priv == NULL) |
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return ERR_PTR(-ENOMEM); |
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priv->hw.init = &init; |
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priv->i2c_dev = i2c_dev; |
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clk_hw_register_clkdev(&priv->hw, "div", dev_name(dev)); |
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return devm_clk_register(dev, &priv->hw); |
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} |
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static void bcm2835_fill_txfifo(struct bcm2835_i2c_dev *i2c_dev) |
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{ |
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u32 val; |
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while (i2c_dev->msg_buf_remaining) { |
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val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); |
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if (!(val & BCM2835_I2C_S_TXD)) |
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break; |
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bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_FIFO, |
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*i2c_dev->msg_buf); |
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i2c_dev->msg_buf++; |
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i2c_dev->msg_buf_remaining--; |
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} |
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} |
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static void bcm2835_drain_rxfifo(struct bcm2835_i2c_dev *i2c_dev) |
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{ |
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u32 val; |
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|
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while (i2c_dev->msg_buf_remaining) { |
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val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); |
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if (!(val & BCM2835_I2C_S_RXD)) |
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break; |
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*i2c_dev->msg_buf = bcm2835_i2c_readl(i2c_dev, |
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BCM2835_I2C_FIFO); |
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i2c_dev->msg_buf++; |
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i2c_dev->msg_buf_remaining--; |
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} |
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} |
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|
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/* |
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* Repeated Start Condition (Sr) |
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* The BCM2835 ARM Peripherals datasheet mentions a way to trigger a Sr when it |
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* talks about reading from a slave with 10 bit address. This is achieved by |
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* issuing a write, poll the I2CS.TA flag and wait for it to be set, and then |
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* issue a read. |
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* A comment in https://github.com/raspberrypi/linux/issues/254 shows how the |
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* firmware actually does it using polling and says that it's a workaround for |
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* a problem in the state machine. |
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* It turns out that it is possible to use the TXW interrupt to know when the |
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* transfer is active, provided the FIFO has not been prefilled. |
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*/ |
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|
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static void bcm2835_i2c_start_transfer(struct bcm2835_i2c_dev *i2c_dev) |
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{ |
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u32 c = BCM2835_I2C_C_ST | BCM2835_I2C_C_I2CEN; |
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struct i2c_msg *msg = i2c_dev->curr_msg; |
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bool last_msg = (i2c_dev->num_msgs == 1); |
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|
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if (!i2c_dev->num_msgs) |
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return; |
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i2c_dev->num_msgs--; |
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i2c_dev->msg_buf = msg->buf; |
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i2c_dev->msg_buf_remaining = msg->len; |
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|
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if (msg->flags & I2C_M_RD) |
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c |= BCM2835_I2C_C_READ | BCM2835_I2C_C_INTR; |
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else |
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c |= BCM2835_I2C_C_INTT; |
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|
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if (last_msg) |
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c |= BCM2835_I2C_C_INTD; |
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bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_A, msg->addr); |
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bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DLEN, msg->len); |
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bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, c); |
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bcm2835_debug_add(i2c_dev, ~0); |
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} |
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|
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static void bcm2835_i2c_finish_transfer(struct bcm2835_i2c_dev *i2c_dev) |
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{ |
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i2c_dev->curr_msg = NULL; |
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i2c_dev->num_msgs = 0; |
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|
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i2c_dev->msg_buf = NULL; |
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i2c_dev->msg_buf_remaining = 0; |
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} |
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|
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/* |
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* Note about I2C_C_CLEAR on error: |
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* The I2C_C_CLEAR on errors will take some time to resolve -- if you were in |
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* non-idle state and I2C_C_READ, it sets an abort_rx flag and runs through |
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* the state machine to send a NACK and a STOP. Since we're setting CLEAR |
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* without I2CEN, that NACK will be hanging around queued up for next time |
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* we start the engine. |
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*/ |
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|
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static irqreturn_t bcm2835_i2c_isr(int this_irq, void *data) |
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{ |
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struct bcm2835_i2c_dev *i2c_dev = data; |
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u32 val, err; |
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|
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val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); |
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bcm2835_debug_add(i2c_dev, val); |
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|
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err = val & (BCM2835_I2C_S_CLKT | BCM2835_I2C_S_ERR); |
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if (err) { |
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i2c_dev->msg_err = err; |
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goto complete; |
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} |
|
|
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if (val & BCM2835_I2C_S_DONE) { |
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if (!i2c_dev->curr_msg) { |
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dev_err(i2c_dev->dev, "Got unexpected interrupt (from firmware?)\n"); |
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} else if (i2c_dev->curr_msg->flags & I2C_M_RD) { |
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bcm2835_drain_rxfifo(i2c_dev); |
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val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); |
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} |
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|
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if ((val & BCM2835_I2C_S_RXD) || i2c_dev->msg_buf_remaining) |
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i2c_dev->msg_err = BCM2835_I2C_S_LEN; |
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else |
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i2c_dev->msg_err = 0; |
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goto complete; |
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} |
|
|
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if (val & BCM2835_I2C_S_TXW) { |
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if (!i2c_dev->msg_buf_remaining) { |
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i2c_dev->msg_err = val | BCM2835_I2C_S_LEN; |
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goto complete; |
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} |
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|
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bcm2835_fill_txfifo(i2c_dev); |
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|
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if (i2c_dev->num_msgs && !i2c_dev->msg_buf_remaining) { |
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i2c_dev->curr_msg++; |
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bcm2835_i2c_start_transfer(i2c_dev); |
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} |
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|
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return IRQ_HANDLED; |
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} |
|
|
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if (val & BCM2835_I2C_S_RXR) { |
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if (!i2c_dev->msg_buf_remaining) { |
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i2c_dev->msg_err = val | BCM2835_I2C_S_LEN; |
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goto complete; |
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} |
|
|
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bcm2835_drain_rxfifo(i2c_dev); |
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return IRQ_HANDLED; |
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} |
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|
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return IRQ_NONE; |
|
|
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complete: |
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bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, BCM2835_I2C_C_CLEAR); |
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bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_S, BCM2835_I2C_S_CLKT | |
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BCM2835_I2C_S_ERR | BCM2835_I2C_S_DONE); |
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complete(&i2c_dev->completion); |
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|
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return IRQ_HANDLED; |
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} |
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|
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static int bcm2835_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], |
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int num) |
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{ |
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struct bcm2835_i2c_dev *i2c_dev = i2c_get_adapdata(adap); |
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unsigned long time_left; |
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int i; |
|
|
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if (debug) |
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i2c_dev->debug_num_msgs = num; |
|
|
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if (debug > 2) |
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for (i = 0; i < num; i++) |
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bcm2835_debug_print_msg(i2c_dev, &msgs[i], i + 1, num, __func__); |
|
|
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for (i = 0; i < (num - 1); i++) |
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if (msgs[i].flags & I2C_M_RD) { |
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dev_warn_once(i2c_dev->dev, |
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"only one read message supported, has to be last\n"); |
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return -EOPNOTSUPP; |
|
} |
|
|
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i2c_dev->curr_msg = msgs; |
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i2c_dev->num_msgs = num; |
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reinit_completion(&i2c_dev->completion); |
|
|
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bcm2835_i2c_start_transfer(i2c_dev); |
|
|
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time_left = wait_for_completion_timeout(&i2c_dev->completion, |
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adap->timeout); |
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|
|
bcm2835_i2c_finish_transfer(i2c_dev); |
|
|
|
if (debug > 1 || (debug && (!time_left || i2c_dev->msg_err))) |
|
bcm2835_debug_print(i2c_dev); |
|
i2c_dev->debug_num_msgs = 0; |
|
i2c_dev->debug_num = 0; |
|
if (!time_left) { |
|
bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, |
|
BCM2835_I2C_C_CLEAR); |
|
dev_err(i2c_dev->dev, "i2c transfer timed out\n"); |
|
return -ETIMEDOUT; |
|
} |
|
|
|
if (!i2c_dev->msg_err) |
|
return num; |
|
|
|
if (debug) |
|
dev_err(i2c_dev->dev, "i2c transfer failed: %x\n", |
|
i2c_dev->msg_err); |
|
|
|
if (i2c_dev->msg_err & BCM2835_I2C_S_ERR) |
|
return -EREMOTEIO; |
|
|
|
return -EIO; |
|
} |
|
|
|
static u32 bcm2835_i2c_func(struct i2c_adapter *adap) |
|
{ |
|
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
|
} |
|
|
|
static const struct i2c_algorithm bcm2835_i2c_algo = { |
|
.master_xfer = bcm2835_i2c_xfer, |
|
.functionality = bcm2835_i2c_func, |
|
}; |
|
|
|
/* |
|
* The BCM2835 was reported to have problems with clock stretching: |
|
* https://www.advamation.com/knowhow/raspberrypi/rpi-i2c-bug.html |
|
* https://www.raspberrypi.org/forums/viewtopic.php?p=146272 |
|
*/ |
|
static const struct i2c_adapter_quirks bcm2835_i2c_quirks = { |
|
.flags = I2C_AQ_NO_CLK_STRETCH, |
|
}; |
|
|
|
static int bcm2835_i2c_probe(struct platform_device *pdev) |
|
{ |
|
struct bcm2835_i2c_dev *i2c_dev; |
|
struct resource *mem, *irq; |
|
int ret; |
|
struct i2c_adapter *adap; |
|
struct clk *mclk; |
|
u32 bus_clk_rate; |
|
|
|
i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); |
|
if (!i2c_dev) |
|
return -ENOMEM; |
|
platform_set_drvdata(pdev, i2c_dev); |
|
i2c_dev->dev = &pdev->dev; |
|
init_completion(&i2c_dev->completion); |
|
|
|
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
|
i2c_dev->regs = devm_ioremap_resource(&pdev->dev, mem); |
|
if (IS_ERR(i2c_dev->regs)) |
|
return PTR_ERR(i2c_dev->regs); |
|
|
|
mclk = devm_clk_get(&pdev->dev, NULL); |
|
if (IS_ERR(mclk)) |
|
return dev_err_probe(&pdev->dev, PTR_ERR(mclk), |
|
"Could not get clock\n"); |
|
|
|
i2c_dev->bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev); |
|
|
|
if (IS_ERR(i2c_dev->bus_clk)) { |
|
dev_err(&pdev->dev, "Could not register clock\n"); |
|
return PTR_ERR(i2c_dev->bus_clk); |
|
} |
|
|
|
ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency", |
|
&bus_clk_rate); |
|
if (ret < 0) { |
|
dev_warn(&pdev->dev, |
|
"Could not read clock-frequency property\n"); |
|
bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ; |
|
} |
|
|
|
ret = clk_set_rate_exclusive(i2c_dev->bus_clk, bus_clk_rate); |
|
if (ret < 0) { |
|
dev_err(&pdev->dev, "Could not set clock frequency\n"); |
|
return ret; |
|
} |
|
|
|
ret = clk_prepare_enable(i2c_dev->bus_clk); |
|
if (ret) { |
|
dev_err(&pdev->dev, "Couldn't prepare clock"); |
|
return ret; |
|
} |
|
|
|
irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); |
|
if (!irq) { |
|
dev_err(&pdev->dev, "No IRQ resource\n"); |
|
return -ENODEV; |
|
} |
|
i2c_dev->irq = irq->start; |
|
|
|
ret = request_irq(i2c_dev->irq, bcm2835_i2c_isr, IRQF_SHARED, |
|
dev_name(&pdev->dev), i2c_dev); |
|
if (ret) { |
|
dev_err(&pdev->dev, "Could not request IRQ\n"); |
|
return -ENODEV; |
|
} |
|
|
|
adap = &i2c_dev->adapter; |
|
i2c_set_adapdata(adap, i2c_dev); |
|
adap->owner = THIS_MODULE; |
|
adap->class = I2C_CLASS_DEPRECATED; |
|
snprintf(adap->name, sizeof(adap->name), "bcm2835 (%s)", |
|
of_node_full_name(pdev->dev.of_node)); |
|
adap->algo = &bcm2835_i2c_algo; |
|
adap->dev.parent = &pdev->dev; |
|
adap->dev.of_node = pdev->dev.of_node; |
|
adap->quirks = of_device_get_match_data(&pdev->dev); |
|
|
|
bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, 0); |
|
|
|
ret = i2c_add_adapter(adap); |
|
if (ret) |
|
free_irq(i2c_dev->irq, i2c_dev); |
|
|
|
return ret; |
|
} |
|
|
|
static int bcm2835_i2c_remove(struct platform_device *pdev) |
|
{ |
|
struct bcm2835_i2c_dev *i2c_dev = platform_get_drvdata(pdev); |
|
|
|
clk_rate_exclusive_put(i2c_dev->bus_clk); |
|
clk_disable_unprepare(i2c_dev->bus_clk); |
|
|
|
free_irq(i2c_dev->irq, i2c_dev); |
|
i2c_del_adapter(&i2c_dev->adapter); |
|
|
|
return 0; |
|
} |
|
|
|
static const struct of_device_id bcm2835_i2c_of_match[] = { |
|
{ .compatible = "brcm,bcm2711-i2c" }, |
|
{ .compatible = "brcm,bcm2835-i2c", .data = &bcm2835_i2c_quirks }, |
|
{}, |
|
}; |
|
MODULE_DEVICE_TABLE(of, bcm2835_i2c_of_match); |
|
|
|
static struct platform_driver bcm2835_i2c_driver = { |
|
.probe = bcm2835_i2c_probe, |
|
.remove = bcm2835_i2c_remove, |
|
.driver = { |
|
.name = "i2c-bcm2835", |
|
.of_match_table = bcm2835_i2c_of_match, |
|
}, |
|
}; |
|
module_platform_driver(bcm2835_i2c_driver); |
|
|
|
MODULE_AUTHOR("Stephen Warren <[email protected]>"); |
|
MODULE_DESCRIPTION("BCM2835 I2C bus adapter"); |
|
MODULE_LICENSE("GPL v2"); |
|
MODULE_ALIAS("platform:i2c-bcm2835");
|
|
|