From 90a50a3b5ff3863c3a3c2fd5959dacaa742b7797 Mon Sep 17 00:00:00 2001 From: Pablo Greco Date: Fri, 29 Mar 2019 18:41:35 +0000 Subject: [PATCH] Reintroduce 80d7fcc321f01c7a69de38a20de726fe8e1149ee --- drivers/i2c/busses/i2c-bcm2835.c | 100 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 99 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c index 4d19254..31d8d9e 100644 --- a/drivers/i2c/busses/i2c-bcm2835.c +++ b/drivers/i2c/busses/i2c-bcm2835.c @@ -56,6 +56,18 @@ #define BCM2835_I2C_CDIV_MIN 0x0002 #define BCM2835_I2C_CDIV_MAX 0xFFFE +static unsigned int debug; +module_param(debug, uint, 0644); +MODULE_PARM_DESC(debug, "1=err, 2=isr, 3=xfer"); + +#define BCM2835_DEBUG_MAX 512 +struct bcm2835_debug { + struct i2c_msg *msg; + int msg_idx; + size_t remain; + u32 status; +}; + struct bcm2835_i2c_dev { struct device *dev; void __iomem *regs; @@ -69,8 +81,78 @@ struct bcm2835_i2c_dev { u32 msg_err; u8 *msg_buf; size_t msg_buf_remaining; + struct bcm2835_debug debug[BCM2835_DEBUG_MAX]; + unsigned int debug_num; + unsigned int debug_num_msgs; }; +static inline void bcm2835_debug_add(struct bcm2835_i2c_dev *i2c_dev, u32 s) +{ + if (!i2c_dev->debug_num_msgs || i2c_dev->debug_num >= BCM2835_DEBUG_MAX) + return; + + i2c_dev->debug[i2c_dev->debug_num].msg = i2c_dev->curr_msg; + i2c_dev->debug[i2c_dev->debug_num].msg_idx = + i2c_dev->debug_num_msgs - i2c_dev->num_msgs; + i2c_dev->debug[i2c_dev->debug_num].remain = i2c_dev->msg_buf_remaining; + i2c_dev->debug[i2c_dev->debug_num].status = s; + i2c_dev->debug_num++; +} + +static void bcm2835_debug_print_status(struct bcm2835_i2c_dev *i2c_dev, + struct bcm2835_debug *d) +{ + u32 s = d->status; + + pr_info("isr: remain=%zu, status=0x%x : %s%s%s%s%s%s%s%s%s%s [i2c%d]\n", + d->remain, s, + s & BCM2835_I2C_S_TA ? "TA " : "", + s & BCM2835_I2C_S_DONE ? "DONE " : "", + s & BCM2835_I2C_S_TXW ? "TXW " : "", + s & BCM2835_I2C_S_RXR ? "RXR " : "", + s & BCM2835_I2C_S_TXD ? "TXD " : "", + s & BCM2835_I2C_S_RXD ? "RXD " : "", + s & BCM2835_I2C_S_TXE ? "TXE " : "", + s & BCM2835_I2C_S_RXF ? "RXF " : "", + s & BCM2835_I2C_S_ERR ? "ERR " : "", + s & BCM2835_I2C_S_CLKT ? "CLKT " : "", + i2c_dev->adapter.nr); +} + +static void bcm2835_debug_print_msg(struct bcm2835_i2c_dev *i2c_dev, + struct i2c_msg *msg, int i, int total, + const char *fname) +{ + pr_info("%s: msg(%d/%d) %s addr=0x%02x, len=%u flags=%s%s%s%s%s%s%s [i2c%d]\n", + fname, i, total, + msg->flags & I2C_M_RD ? "read" : "write", msg->addr, msg->len, + msg->flags & I2C_M_TEN ? "TEN" : "", + msg->flags & I2C_M_RECV_LEN ? "RECV_LEN" : "", + msg->flags & I2C_M_NO_RD_ACK ? "NO_RD_ACK" : "", + msg->flags & I2C_M_IGNORE_NAK ? "IGNORE_NAK" : "", + msg->flags & I2C_M_REV_DIR_ADDR ? "REV_DIR_ADDR" : "", + msg->flags & I2C_M_NOSTART ? "NOSTART" : "", + msg->flags & I2C_M_STOP ? "STOP" : "", + i2c_dev->adapter.nr); +} + +static void bcm2835_debug_print(struct bcm2835_i2c_dev *i2c_dev) +{ + struct bcm2835_debug *d; + unsigned int i; + + for (i = 0; i < i2c_dev->debug_num; i++) { + d = &i2c_dev->debug[i]; + if (d->status == ~0) + bcm2835_debug_print_msg(i2c_dev, d->msg, d->msg_idx, + i2c_dev->debug_num_msgs, "start_transfer"); + else + bcm2835_debug_print_status(i2c_dev, d); + } + if (i2c_dev->debug_num >= BCM2835_DEBUG_MAX) + pr_info("BCM2835_DEBUG_MAX reached\n"); +} + static inline void bcm2835_i2c_writel(struct bcm2835_i2c_dev *i2c_dev, u32 reg, u32 val) { @@ -189,6 +271,7 @@ static void bcm2835_i2c_start_transfer(struct bcm2835_i2c_dev *i2c_dev) bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_A, msg->addr); bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DLEN, msg->len); bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, c); + bcm2835_debug_add(i2c_dev, ~0); } static void bcm2835_i2c_finish_transfer(struct bcm2835_i2c_dev *i2c_dev) @@ -215,6 +298,7 @@ static irqreturn_t bcm2835_i2c_isr(int this_irq, void *data) u32 val, err; val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); + bcm2835_debug_add(i2c_dev, val); err = val & (BCM2835_I2C_S_CLKT | BCM2835_I2C_S_ERR); if (err) { @@ -281,6 +365,13 @@ static int bcm2835_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], unsigned long time_left; int i, ret; + if (debug) + i2c_dev->debug_num_msgs = num; + + if (debug > 2) + for (i = 0; i < num; i++) + bcm2835_debug_print_msg(i2c_dev, &msgs[i], i + 1, num, __func__); + for (i = 0; i < (num - 1); i++) if (msgs[i].flags & I2C_M_RD) { dev_warn_once(i2c_dev->dev, @@ -303,6 +394,11 @@ static int bcm2835_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], 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); @@ -313,7 +409,9 @@ static int bcm2835_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], if (!i2c_dev->msg_err) return num; - dev_dbg(i2c_dev->dev, "i2c transfer failed: %x\n", i2c_dev->msg_err); + 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; -- 1.8.3.1