| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1360923110-21692-1-git-send-email-christian.ruppert@abilis.com>
Date: Fri, 15 Feb 2013 11:11:50 +0100
From: Christian Ruppert <christian.ruppert@...lis.com>
To: Wolfram Sang <w.sang@...gutronix.de>,
"Ben Dooks (embedded platforms)" <ben-linux@...ff.org>
Cc: Grant Likely <grant.likely@...retlab.ca>,
Rob Herring <rob.herring@...xeda.com>,
Rob Landley <rob@...dley.net>,
devicetree-discuss@...ts.ozlabs.org, linux-doc@...r.kernel.org,
linux-kernel@...r.kernel.org, linux-i2c@...r.kernel.org,
Vineet Gupta <Vineet.Gupta1@...opsys.com>,
Christian Ruppert <christian.ruppert@...lis.com>,
Pierrick Hascoet <pierrick.hascoet@...lis.com>
Subject: [PATCH] i2c-designware: Interrupt sharing and SDA hold time
This patch implements interrupt sharing and SDA hold time configuration in
the designware i2c driver. Both functions are enabled through platform data
or device tree. Tested with Linux-3.8rc4 (Synopsys ARC port, see
https://github.com/foss-for-synopsys-dwc-arc-processors/linux/commits/arc-3.8-baseline).
Signed-off-by: Christian Ruppert <christian.ruppert@...lis.com>
Signed-off-by: Pierrick Hascoet <pierrick.hascoet@...lis.com>
---
.../devicetree/bindings/i2c/i2c-designware.txt | 18 ++++++++++
drivers/i2c/busses/i2c-designware-core.c | 6 +++
drivers/i2c/busses/i2c-designware-core.h | 2 +
drivers/i2c/busses/i2c-designware-platdrv.c | 34 +++++++++++++++++++-
include/linux/i2c/i2c-designware.h | 13 +++++++
5 files changed, 72 insertions(+), 1 deletions(-)
create mode 100644 include/linux/i2c/i2c-designware.h
diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt
index e42a2ee..474386b 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt
@@ -10,6 +10,12 @@ Recommended properties :
- clock-frequency : desired I2C bus clock frequency in Hz.
+Optional properties :
+ - interrupts-shared : If this property is present, the interrupt line is
+ considered shared with other devices.
+ - sda-hold-time : If this property is present, the register SDA_HOLD will
+ be initialised with its value.
+
Example :
i2c@...00 {
@@ -20,3 +26,15 @@ Example :
interrupts = <11>;
clock-frequency = <400000>;
};
+
+ i2c@...0000 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "snps,designware-i2c";
+ reg = <0x1120000 0x1000>;
+ interrupt-parent = <&ictl>;
+ interrupts = <12 1>;
+ interrupts-shared;
+ clock-frequency = <400000>;
+ sda-hold-time = <0x64>;
+ };
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index cbba7db..36ba0b5 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -34,6 +34,7 @@
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <linux/delay.h>
+#include <linux/i2c/i2c-designware.h>
#include "i2c-designware-core.h"
/*
@@ -66,6 +67,7 @@
#define DW_IC_STATUS 0x70
#define DW_IC_TXFLR 0x74
#define DW_IC_RXFLR 0x78
+#define DW_IC_SDA_HOLD 0x7c
#define DW_IC_TX_ABRT_SOURCE 0x80
#define DW_IC_COMP_PARAM_1 0xf4
#define DW_IC_COMP_TYPE 0xfc
@@ -309,6 +311,10 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT);
dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
+ /* Configure SDA Hold Time if required */
+ if (dev->pdat_flags & I2C_DW_PDAT_FLAGS_SET_HOLDTIME)
+ dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD);
+
/* Configure Tx/Rx FIFO threshold levels */
dw_writel(dev, dev->tx_fifo_depth - 1, DW_IC_TX_TL);
dw_writel(dev, 0, DW_IC_RX_TL);
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 9c1840e..ef20477 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -88,6 +88,8 @@ struct dw_i2c_dev {
u32 master_cfg;
unsigned int tx_fifo_depth;
unsigned int rx_fifo_depth;
+ u32 sda_hold_time;
+ unsigned int pdat_flags;
};
#define ACCESS_SWAP 0x00000001
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 343357a..2ad2da3 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -34,11 +34,13 @@
#include <linux/sched.h>
#include <linux/err.h>
#include <linux/interrupt.h>
+#include <linux/of.h>
#include <linux/of_i2c.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/io.h>
#include <linux/slab.h>
+#include <linux/i2c/i2c-designware.h>
#include "i2c-designware-core.h"
static struct i2c_algorithm i2c_dw_algo = {
@@ -56,6 +58,28 @@ static int dw_i2c_probe(struct platform_device *pdev)
struct i2c_adapter *adap;
struct resource *mem, *ioarea;
int irq, r;
+ unsigned long irqf;
+ struct i2c_designware_platform_data *pdat = pdev->dev.platform_data;
+
+ if ((!pdat) && pdev->dev.of_node) {
+ struct device_node *node = pdev->dev.of_node;
+
+ pdat = kmalloc(sizeof(struct i2c_designware_platform_data),
+ GFP_KERNEL);
+ if (!pdat)
+ return -ENOMEM;
+
+ pdat->flags = 0;
+
+ if (of_get_property(node, "interrupts-shared", NULL))
+ pdat->flags |= I2C_DW_PDAT_FLAGS_SHARE_IRQ;
+
+ if (!of_property_read_u32(node, "sda-hold-time",
+ &pdat->sda_hold_time))
+ pdat->flags |= I2C_DW_PDAT_FLAGS_SET_HOLDTIME;
+
+ pdev->dev.platform_data = pdat;
+ }
/* NOTE: driver uses the static register mapping */
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -120,12 +144,20 @@ static int dw_i2c_probe(struct platform_device *pdev)
dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
}
+ dev->sda_hold_time = pdat->sda_hold_time;
+ dev->pdat_flags = pdat->flags;
+
r = i2c_dw_init(dev);
if (r)
goto err_iounmap;
i2c_dw_disable_int(dev);
- r = request_irq(dev->irq, i2c_dw_isr, IRQF_DISABLED, pdev->name, dev);
+
+ irqf = IRQF_DISABLED;
+ if (dev->pdat_flags & I2C_DW_PDAT_FLAGS_SHARE_IRQ)
+ irqf |= IRQF_SHARED;
+
+ r = request_irq(dev->irq, i2c_dw_isr, irqf, pdev->name, dev);
if (r) {
dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
goto err_iounmap;
diff --git a/include/linux/i2c/i2c-designware.h b/include/linux/i2c/i2c-designware.h
new file mode 100644
index 0000000..ea8192a
--- /dev/null
+++ b/include/linux/i2c/i2c-designware.h
@@ -0,0 +1,13 @@
+#ifndef __I2C_DESIGNWARE_H__
+#define __I2C_DESIGNWARE_H__
+
+#include <linux/platform_device.h>
+
+struct i2c_designware_platform_data {
+ unsigned int flags;
+#define I2C_DW_PDAT_FLAGS_SHARE_IRQ (1L<<0)
+#define I2C_DW_PDAT_FLAGS_SET_HOLDTIME (1L<<1)
+ u32 sda_hold_time;
+};
+
+#endif /* __I2C_DESIGNWARE_H__ */
--
1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists