* [PATCH v3 0/3] i2c-designware: Allow mixed endianness
@ 2010-01-27 19:19 Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 1/3] i2c-designware: Use local version of readl & writel Jean-Hugues Deschenes
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Jean-Hugues Deschenes @ 2010-01-27 19:19 UTC (permalink / raw)
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA; +Cc: Ben Dooks, Baruch Siach
This is the v3 version of the patch which adds support
for the i2c Designware controller when its endianness
differs from that of the cpu.
Signed-off-by: Jean-Hugues Deschenes <jean-hugues.deschenes-YGVykHU+fedBDgjK7y7TUQ@public.gmane.org>
---
Changelog v2->v3
- use a single variable for reading COMP_TYPE and PARAM_1 (Ben Dooks)
Changelog v1->v2
- rename i2c_dw_(read|write)l to dw_(read|write)l (Shinya Kuribayashi)
- rename dw_(read|write)l's addr argument to offset (Shinya Kuribayashi)
- replace (if constant == x) with (if x == constant) (Ben Dooks)
---
--
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v3 1/3] i2c-designware: Use local version of readl & writel
2010-01-27 19:19 [PATCH v3 0/3] i2c-designware: Allow mixed endianness Jean-Hugues Deschenes
@ 2010-01-27 19:19 ` Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 2/3] i2c-designware: Check component type register Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 3/3] i2c-designware: Allow mixed endianness accesses Jean-Hugues Deschenes
2 siblings, 0 replies; 4+ messages in thread
From: Jean-Hugues Deschenes @ 2010-01-27 19:19 UTC (permalink / raw)
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA
Cc: Ben Dooks, Baruch Siach, Jean-Hugues Deschenes
[-- Attachment #1: use_local_readl_writel --]
[-- Type: text/plain, Size: 8275 bytes --]
Use local versions of readl & writel, so per-access manipulations may be performed
Signed-off-by: Jean-Hugues Deschenes <jean-hugues.deschenes-YGVykHU+fedBDgjK7y7TUQ@public.gmane.org>
---
drivers/i2c/busses/i2c-designware.c | 88 ++++++++++++++++++++----------------
1 file changed, 49 insertions(+), 39 deletions(-)
Index: linux-2.6_i2c/drivers/i2c/busses/i2c-designware.c
===================================================================
--- linux-2.6_i2c.orig/drivers/i2c/busses/i2c-designware.c
+++ linux-2.6_i2c/drivers/i2c/busses/i2c-designware.c
@@ -219,6 +219,16 @@ struct dw_i2c_dev {
unsigned int rx_fifo_depth;
};
+static u32 dw_readl(struct dw_i2c_dev *dev, int offset)
+{
+ return readl(dev->base + offset);
+}
+
+static void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
+{
+ writel(b, dev->base + offset);
+}
+
static u32
i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset)
{
@@ -288,7 +298,7 @@ static void i2c_dw_init(struct dw_i2c_de
u32 ic_con, hcnt, lcnt;
/* Disable the adapter */
- writel(0, dev->base + DW_IC_ENABLE);
+ dw_writel(dev, 0, DW_IC_ENABLE);
/* set standard and fast speed deviders for high/low periods */
@@ -302,8 +312,8 @@ static void i2c_dw_init(struct dw_i2c_de
47, /* tLOW = 4.7 us */
3, /* tf = 0.3 us */
0); /* No offset */
- writel(hcnt, dev->base + DW_IC_SS_SCL_HCNT);
- writel(lcnt, dev->base + DW_IC_SS_SCL_LCNT);
+ dw_writel(dev, hcnt, DW_IC_SS_SCL_HCNT);
+ dw_writel(dev, lcnt, DW_IC_SS_SCL_LCNT);
dev_dbg(dev->dev, "Standard-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
/* Fast-mode */
@@ -316,18 +326,18 @@ static void i2c_dw_init(struct dw_i2c_de
13, /* tLOW = 1.3 us */
3, /* tf = 0.3 us */
0); /* No offset */
- writel(hcnt, dev->base + DW_IC_FS_SCL_HCNT);
- writel(lcnt, dev->base + DW_IC_FS_SCL_LCNT);
+ dw_writel(dev, hcnt, DW_IC_FS_SCL_HCNT);
+ dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT);
dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
/* Configure Tx/Rx FIFO threshold levels */
- writel(dev->tx_fifo_depth - 1, dev->base + DW_IC_TX_TL);
- writel(0, dev->base + DW_IC_RX_TL);
+ dw_writel(dev, dev->tx_fifo_depth - 1, DW_IC_TX_TL);
+ dw_writel(dev, 0, DW_IC_RX_TL);
/* configure the i2c master */
ic_con = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
- writel(ic_con, dev->base + DW_IC_CON);
+ dw_writel(dev, ic_con, DW_IC_CON);
}
/*
@@ -337,7 +347,7 @@ static int i2c_dw_wait_bus_not_busy(stru
{
int timeout = TIMEOUT;
- while (readl(dev->base + DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY) {
+ while (dw_readl(dev, DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY) {
if (timeout <= 0) {
dev_warn(dev->dev, "timeout waiting for bus ready\n");
return -ETIMEDOUT;
@@ -355,24 +365,24 @@ static void i2c_dw_xfer_init(struct dw_i
u32 ic_con;
/* Disable the adapter */
- writel(0, dev->base + DW_IC_ENABLE);
+ dw_writel(dev, 0, DW_IC_ENABLE);
/* set the slave (target) address */
- writel(msgs[dev->msg_write_idx].addr, dev->base + DW_IC_TAR);
+ dw_writel(dev, msgs[dev->msg_write_idx].addr, DW_IC_TAR);
/* if the slave address is ten bit address, enable 10BITADDR */
- ic_con = readl(dev->base + DW_IC_CON);
+ ic_con = dw_readl(dev, DW_IC_CON);
if (msgs[dev->msg_write_idx].flags & I2C_M_TEN)
ic_con |= DW_IC_CON_10BITADDR_MASTER;
else
ic_con &= ~DW_IC_CON_10BITADDR_MASTER;
- writel(ic_con, dev->base + DW_IC_CON);
+ dw_writel(dev, ic_con, DW_IC_CON);
/* Enable the adapter */
- writel(1, dev->base + DW_IC_ENABLE);
+ dw_writel(dev, 1, DW_IC_ENABLE);
/* Enable interrupts */
- writel(DW_IC_INTR_DEFAULT_MASK, dev->base + DW_IC_INTR_MASK);
+ dw_writel(dev, DW_IC_INTR_DEFAULT_MASK, DW_IC_INTR_MASK);
}
/*
@@ -419,15 +429,15 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
buf_len = msgs[dev->msg_write_idx].len;
}
- tx_limit = dev->tx_fifo_depth - readl(dev->base + DW_IC_TXFLR);
- rx_limit = dev->rx_fifo_depth - readl(dev->base + DW_IC_RXFLR);
+ tx_limit = dev->tx_fifo_depth - dw_readl(dev, DW_IC_TXFLR);
+ rx_limit = dev->rx_fifo_depth - dw_readl(dev, DW_IC_RXFLR);
while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) {
if (msgs[dev->msg_write_idx].flags & I2C_M_RD) {
- writel(0x100, dev->base + DW_IC_DATA_CMD);
+ dw_writel(dev, 0x100, DW_IC_DATA_CMD);
rx_limit--;
} else
- writel(*buf++, dev->base + DW_IC_DATA_CMD);
+ dw_writel(dev, *buf++, DW_IC_DATA_CMD);
tx_limit--; buf_len--;
}
@@ -452,7 +462,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
if (dev->msg_err)
intr_mask = 0;
- writel(intr_mask, dev->base + DW_IC_INTR_MASK);
+ dw_writel(dev, intr_mask, DW_IC_INTR_MASK);
}
static void
@@ -476,10 +486,10 @@ i2c_dw_read(struct dw_i2c_dev *dev)
buf = dev->rx_buf;
}
- rx_valid = readl(dev->base + DW_IC_RXFLR);
+ rx_valid = dw_readl(dev, DW_IC_RXFLR);
for (; len > 0 && rx_valid > 0; len--, rx_valid--)
- *buf++ = readl(dev->base + DW_IC_DATA_CMD);
+ *buf++ = dw_readl(dev, DW_IC_DATA_CMD);
if (len > 0) {
dev->status |= STATUS_READ_IN_PROGRESS;
@@ -562,7 +572,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, st
/* no error */
if (likely(!dev->cmd_err)) {
/* Disable the adapter */
- writel(0, dev->base + DW_IC_ENABLE);
+ dw_writel(dev, 0, DW_IC_ENABLE);
ret = num;
goto done;
}
@@ -606,7 +616,7 @@ static u32 i2c_dw_read_clear_intrbits(st
*
* The raw version might be useful for debugging purposes.
*/
- stat = readl(dev->base + DW_IC_INTR_STAT);
+ stat = dw_readl(dev, DW_IC_INTR_STAT);
/*
* Do not use the IC_CLR_INTR register to clear interrupts, or
@@ -616,31 +626,31 @@ static u32 i2c_dw_read_clear_intrbits(st
* Instead, use the separately-prepared IC_CLR_* registers.
*/
if (stat & DW_IC_INTR_RX_UNDER)
- readl(dev->base + DW_IC_CLR_RX_UNDER);
+ dw_readl(dev, DW_IC_CLR_RX_UNDER);
if (stat & DW_IC_INTR_RX_OVER)
- readl(dev->base + DW_IC_CLR_RX_OVER);
+ dw_readl(dev, DW_IC_CLR_RX_OVER);
if (stat & DW_IC_INTR_TX_OVER)
- readl(dev->base + DW_IC_CLR_TX_OVER);
+ dw_readl(dev, DW_IC_CLR_TX_OVER);
if (stat & DW_IC_INTR_RD_REQ)
- readl(dev->base + DW_IC_CLR_RD_REQ);
+ dw_readl(dev, DW_IC_CLR_RD_REQ);
if (stat & DW_IC_INTR_TX_ABRT) {
/*
* The IC_TX_ABRT_SOURCE register is cleared whenever
* the IC_CLR_TX_ABRT is read. Preserve it beforehand.
*/
- dev->abort_source = readl(dev->base + DW_IC_TX_ABRT_SOURCE);
- readl(dev->base + DW_IC_CLR_TX_ABRT);
+ dev->abort_source = dw_readl(dev, DW_IC_TX_ABRT_SOURCE);
+ dw_readl(dev, DW_IC_CLR_TX_ABRT);
}
if (stat & DW_IC_INTR_RX_DONE)
- readl(dev->base + DW_IC_CLR_RX_DONE);
+ dw_readl(dev, DW_IC_CLR_RX_DONE);
if (stat & DW_IC_INTR_ACTIVITY)
- readl(dev->base + DW_IC_CLR_ACTIVITY);
+ dw_readl(dev, DW_IC_CLR_ACTIVITY);
if (stat & DW_IC_INTR_STOP_DET)
- readl(dev->base + DW_IC_CLR_STOP_DET);
+ dw_readl(dev, DW_IC_CLR_STOP_DET);
if (stat & DW_IC_INTR_START_DET)
- readl(dev->base + DW_IC_CLR_START_DET);
+ dw_readl(dev, DW_IC_CLR_START_DET);
if (stat & DW_IC_INTR_GEN_CALL)
- readl(dev->base + DW_IC_CLR_GEN_CALL);
+ dw_readl(dev, DW_IC_CLR_GEN_CALL);
return stat;
}
@@ -665,7 +675,7 @@ static irqreturn_t i2c_dw_isr(int this_i
* Anytime TX_ABRT is set, the contents of the tx/rx
* buffers are flushed. Make sure to skip them.
*/
- writel(0, dev->base + DW_IC_INTR_MASK);
+ dw_writel(dev, 0, DW_IC_INTR_MASK);
goto tx_aborted;
}
@@ -746,14 +756,14 @@ static int __devinit dw_i2c_probe(struct
goto err_unuse_clocks;
}
{
- u32 param1 = readl(dev->base + DW_IC_COMP_PARAM_1);
+ u32 param1 = dw_readl(dev, DW_IC_COMP_PARAM_1);
dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
}
i2c_dw_init(dev);
- writel(0, dev->base + DW_IC_INTR_MASK); /* disable IRQ */
+ dw_writel(dev, 0, DW_IC_INTR_MASK); /* disable IRQ */
r = request_irq(dev->irq, i2c_dw_isr, IRQF_DISABLED, pdev->name, dev);
if (r) {
dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
@@ -809,7 +819,7 @@ static int __devexit dw_i2c_remove(struc
clk_put(dev->clk);
dev->clk = NULL;
- writel(0, dev->base + DW_IC_ENABLE);
+ dw_writel(dev, 0, DW_IC_ENABLE);
free_irq(dev->irq, dev);
kfree(dev);
--
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v3 2/3] i2c-designware: Check component type register
2010-01-27 19:19 [PATCH v3 0/3] i2c-designware: Allow mixed endianness Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 1/3] i2c-designware: Use local version of readl & writel Jean-Hugues Deschenes
@ 2010-01-27 19:19 ` Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 3/3] i2c-designware: Allow mixed endianness accesses Jean-Hugues Deschenes
2 siblings, 0 replies; 4+ messages in thread
From: Jean-Hugues Deschenes @ 2010-01-27 19:19 UTC (permalink / raw)
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA
Cc: Ben Dooks, Baruch Siach, Jean-Hugues Deschenes
[-- Attachment #1: check_dw_component --]
[-- Type: text/plain, Size: 1666 bytes --]
Designware component type register is checked before attaching to the device.
Signed-off-by: Jean-Hugues Deschenes <jean-hugues.deschenes-YGVykHU+fedBDgjK7y7TUQ@public.gmane.org>
---
drivers/i2c/busses/i2c-designware.c | 11 +++++++++++
1 file changed, 11 insertions(+)
Index: linux-2.6_i2c/drivers/i2c/busses/i2c-designware.c
===================================================================
--- linux-2.6_i2c.orig/drivers/i2c/busses/i2c-designware.c
+++ linux-2.6_i2c/drivers/i2c/busses/i2c-designware.c
@@ -68,6 +68,7 @@
#define DW_IC_TXFLR 0x74
#define DW_IC_RXFLR 0x78
#define DW_IC_COMP_PARAM_1 0xf4
+#define DW_IC_COMP_TYPE 0xfc
#define DW_IC_TX_ABRT_SOURCE 0x80
#define DW_IC_CON_MASTER 0x1
@@ -709,6 +710,7 @@ static int __devinit dw_i2c_probe(struct
struct i2c_adapter *adap;
struct resource *mem, *ioarea;
int irq, r;
+ u32 reg;
/* NOTE: driver uses the static register mapping */
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -755,12 +757,19 @@ static int __devinit dw_i2c_probe(struct
r = -EBUSY;
goto err_unuse_clocks;
}
- {
- u32 param1 = dw_readl(dev, DW_IC_COMP_PARAM_1);
- dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
- dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
+ reg = dw_readl(dev, DW_IC_COMP_TYPE);
+ if (reg != 0x44570140) {
+ dev_err(&pdev->dev, "Unknown Synopsys component type: "
+ "0x%08x\n", reg);
+ r = -ENODEV;
+ goto err_iounmap;
}
+
+ reg = dw_readl(dev, DW_IC_COMP_PARAM_1);
+ dev->tx_fifo_depth = ((reg >> 16) & 0xff) + 1;
+ dev->rx_fifo_depth = ((reg >> 8) & 0xff) + 1;
+
i2c_dw_init(dev);
dw_writel(dev, 0, DW_IC_INTR_MASK); /* disable IRQ */
--
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v3 3/3] i2c-designware: Allow mixed endianness accesses
2010-01-27 19:19 [PATCH v3 0/3] i2c-designware: Allow mixed endianness Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 1/3] i2c-designware: Use local version of readl & writel Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 2/3] i2c-designware: Check component type register Jean-Hugues Deschenes
@ 2010-01-27 19:19 ` Jean-Hugues Deschenes
2 siblings, 0 replies; 4+ messages in thread
From: Jean-Hugues Deschenes @ 2010-01-27 19:19 UTC (permalink / raw)
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA
Cc: Ben Dooks, Baruch Siach, Jean-Hugues Deschenes
[-- Attachment #1: allow_mixed_endianness --]
[-- Type: text/plain, Size: 2134 bytes --]
Allows CPUs of a given endianness to access a dw controller of a different
endianness. Endianncess difference is detected at run time through the dw
component type register.
Signed-off-by: Jean-Hugues Deschenes <jean-hugues.deschenes-YGVykHU+fedBDgjK7y7TUQ@public.gmane.org>
---
drivers/i2c/busses/i2c-designware.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
Index: linux-2.6_i2c/drivers/i2c/busses/i2c-designware.c
===================================================================
--- linux-2.6_i2c.orig/drivers/i2c/busses/i2c-designware.c
+++ linux-2.6_i2c/drivers/i2c/busses/i2c-designware.c
@@ -36,6 +36,7 @@
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/io.h>
+#include <linux/swab.h>
/*
* Registers offset
@@ -192,6 +193,7 @@ static char *abort_sources[] = {
* @status: i2c master status, one of STATUS_*
* @abort_source: copy of the TX_ABRT_SOURCE register
* @irq: interrupt number for the i2c master
+ * @swab: true if the instantiated IP is of different endianess
* @adapter: i2c subsystem adapter node
* @tx_fifo_depth: depth of the hardware tx fifo
* @rx_fifo_depth: depth of the hardware rx fifo
@@ -215,6 +217,7 @@ struct dw_i2c_dev {
unsigned int status;
u32 abort_source;
int irq;
+ int swab;
struct i2c_adapter adapter;
unsigned int tx_fifo_depth;
unsigned int rx_fifo_depth;
@@ -222,11 +225,19 @@ struct dw_i2c_dev {
static u32 dw_readl(struct dw_i2c_dev *dev, int offset)
{
- return readl(dev->base + offset);
+ u32 value = readl(dev->base + offset);
+
+ if (dev->swab)
+ return swab32(value);
+ else
+ return value;
}
static void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
{
+ if (dev->swab)
+ b = swab32(b);
+
writel(b, dev->base + offset);
}
@@ -759,7 +770,9 @@ static int __devinit dw_i2c_probe(struct
}
reg = dw_readl(dev, DW_IC_COMP_TYPE);
- if (reg != 0x44570140) {
+ if (reg == ___constant_swab32(0x44570140))
+ dev->swab = 1;
+ else if (reg != 0x44570140) {
dev_err(&pdev->dev, "Unknown Synopsys component type: "
"0x%08x\n", reg);
r = -ENODEV;
--
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2010-01-27 19:19 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2010-01-27 19:19 [PATCH v3 0/3] i2c-designware: Allow mixed endianness Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 1/3] i2c-designware: Use local version of readl & writel Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 2/3] i2c-designware: Check component type register Jean-Hugues Deschenes
2010-01-27 19:19 ` [PATCH v3 3/3] i2c-designware: Allow mixed endianness accesses Jean-Hugues Deschenes
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