From patchwork Sat Oct 6 12:45:47 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell King X-Patchwork-Id: 1557501 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id EA5863FD56 for ; Sat, 6 Oct 2012 12:45:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756123Ab2JFMp5 (ORCPT ); Sat, 6 Oct 2012 08:45:57 -0400 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:47330 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756032Ab2JFMp4 (ORCPT ); Sat, 6 Oct 2012 08:45:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=arm.linux.org.uk; s=caramon; h=Date:Sender:Message-Id:Subject:Cc:To:From:References:In-Reply-To; bh=GY33Uub1k/llk8O/BuUfXujDA0Ubo0H1lESE8k+XR8I=; b=SNrHfJDeFrLooNiO10c3O3pjnvlHBHecnhr9FIroNDktaah9rQs6x22L6ljBa6A9V9t5wHUVv1BOSpbGiJsT8cB1kMKghNwgU8UvN7ukd9PM+Ex/4jRdzzZZxCRMltkC6AJ7Gapip7my5vn7kC1k4Z/A5gpaVhDydDYxMGaNT6Y=; Received: from e0022681537dd.dyn.arm.linux.org.uk ([2002:4e20:1eda:1:222:68ff:fe15:37dd]:39611 helo=rmk-PC.arm.linux.org.uk) by caramon.arm.linux.org.uk with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.76) (envelope-from ) id 1TKTlM-00089v-6X; Sat, 06 Oct 2012 13:45:48 +0100 Received: from rmk by rmk-PC.arm.linux.org.uk with local (Exim 4.76) (envelope-from ) id 1TKTlL-0002ni-MB; Sat, 06 Oct 2012 13:45:47 +0100 In-Reply-To: <20121006123803.GD15246@n2100.arm.linux.org.uk> References: <20121006123803.GD15246@n2100.arm.linux.org.uk> From: Russell King To: Tony Lindgren , Alan Cox , Greg Kroah-Hartman Cc: linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, linux-serial@vger.kernel.org Subject: [RFC 20/24] SERIAL: core: add xmit buffer allocation callbacks Message-Id: Date: Sat, 06 Oct 2012 13:45:47 +0100 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org This allows drivers (such as OMAP serial) to allocate and free their transmit buffers in a sane manner, rather than working around the buffer allocation provided by serial_core. Signed-off-by: Russell King --- drivers/tty/serial/serial_core.c | 23 ++++++++++++++++------- include/linux/serial_core.h | 2 ++ 2 files changed, 18 insertions(+), 7 deletions(-) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 4dd609e..53274ae 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -147,12 +147,18 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state, * buffer. */ if (!state->xmit.buf) { - /* This is protected by the per port mutex */ - page = get_zeroed_page(GFP_KERNEL); - if (!page) - return -ENOMEM; + if (uport->ops->alloc_xmit) { + retval = uport->ops->alloc_xmit(uport, &state->xmit); + if (retval) + return retval; + } else { + /* This is protected by the per port mutex */ + page = get_zeroed_page(GFP_KERNEL); + if (!page) + return -ENOMEM; - state->xmit.buf = (unsigned char *) page; + state->xmit.buf = (unsigned char *) page; + } uart_circ_clear(&state->xmit); } @@ -257,7 +263,10 @@ static void uart_shutdown(struct tty_struct *tty, struct uart_state *state) * Free the transmit buffer page. */ if (state->xmit.buf) { - free_page((unsigned long)state->xmit.buf); + if (uport->ops->free_xmit) + uport->ops->free_xmit(uport, &state->xmit); + else + free_page((unsigned long)state->xmit.buf); state->xmit.buf = NULL; } } diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index b17d4c9..ebe9af1 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -248,6 +248,8 @@ struct uart_ops { void (*break_ctl)(struct uart_port *, int ctl); int (*startup)(struct uart_port *); void (*shutdown)(struct uart_port *); + int (*alloc_xmit)(struct uart_port *, struct circ_buf *); + void (*free_xmit)(struct uart_port *, struct circ_buf *); void (*flush_buffer)(struct uart_port *); void (*set_termios)(struct uart_port *, struct ktermios *new, struct ktermios *old);