From mboxrd@z Thu Jan 1 00:00:00 1970 From: Samu Onkalo Subject: [PATCH 1/2] drivers: i2c-core: Add a flag to allow short timeout Date: Wed, 13 Oct 2010 16:45:09 +0300 Message-ID: <1286977510-16702-2-git-send-email-samu.p.onkalo@nokia.com> References: <1286977510-16702-1-git-send-email-samu.p.onkalo@nokia.com> Return-path: In-Reply-To: <1286977510-16702-1-git-send-email-samu.p.onkalo-xNZwKgViW5gAvxtiuMwx3w@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org, tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org A flag for i2c-messages to allow short time out. Some chips causes time out always with certain kind of operations (like sw-reset commands). There is no point of waiting full timeout in that case. When I2C message is send with I2C_M_SHORT_TIME out flag, adapter is allowed to use shorter timeout and release the bus faster. Signed-off-by: Samu Onkalo --- drivers/i2c/i2c-core.c | 2 +- include/linux/i2c.h | 1 + 2 files changed, 2 insertions(+), 1 deletions(-) diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 6649176..8c0e443 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -2077,7 +2077,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, int try; s32 res; - flags &= I2C_M_TEN | I2C_CLIENT_PEC; + flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_M_SHORT_TIMEOUT; if (adapter->algo->smbus_xfer) { i2c_lock_adapter(adapter); diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 4bae0b7..5fc016a 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -514,6 +514,7 @@ struct i2c_msg { #define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */ #define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */ #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */ +#define I2C_M_SHORT_TIMEOUT 0x0200 /* Use with known timeout cases */ __u16 len; /* msg length */ __u8 *buf; /* pointer to msg data */ }; -- 1.6.0.4