Subject: [PATCHv2 2/4] mailbox: Introduce a new common API

From: [email-masked] (Suman Anna)
Date: Thu, 9 May 2013 11:31:07 -0500

Hi Jassi,

On 05/06/2013 02:24 AM, Jassi Brar wrote:
> +++ b/include/linux/mailbox_client.h
> @@ -0,0 +1,85 @@
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#ifndef __MAILBOX_CLIENT_H
> +#define __MAILBOX_CLIENT_H
> +
> +#include <linux/mailbox.h>
> +
> +/**
> + * struct ipc_client - User of a mailbox
> + * @chan_name: the "controller:channel" this client wants
> + * @rxcb: atomic callback to provide client the data received
> + * @txcb: atomic callback to tell client of data transmission
> + * @tx_block: if the ipc_send_message should block until data is transmitted
> + * @tx_tout: Max block period in ms before TX is assumed failure
> + * @knows_txdone: if the client could run the TX state machine. Usually if
> + *    the client receives some ACK packet for transmission. Unused if the
> + *    controller already has TX_Done/RTR IRQ.
> + * @cntlr_data: Optional controller specific parameters during channel request
> + */
> +struct ipc_client {
> +	char *chan_name;
> +	void (*rxcb)(void *data);
> +	void (*txcb)(request_token_t t, enum xfer_result r);

We have to introduce a callback data pointer, so that the calling
clients can retrieve a context object variable or some other useful
data within the callback functions, just like most normal callback
function declarations and registrations do.

> +	bool tx_block;
> +	unsigned long tx_tout;
> +	bool knows_txdone;
> +	void *cntlr_data;
> +};

regards
Suman