From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BE0EEC64E7B for ; Fri, 20 Nov 2020 04:52:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C1B42236F for ; Fri, 20 Nov 2020 04:52:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726444AbgKTEvq (ORCPT ); Thu, 19 Nov 2020 23:51:46 -0500 Received: from kvm5.telegraphics.com.au ([98.124.60.144]:52760 "EHLO kvm5.telegraphics.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726293AbgKTEvi (ORCPT ); Thu, 19 Nov 2020 23:51:38 -0500 Received: by kvm5.telegraphics.com.au (Postfix, from userid 502) id 2F5FA2A45C; Thu, 19 Nov 2020 23:51:37 -0500 (EST) To: Benjamin Herrenschmidt , Michael Ellerman Cc: "Joshua Thompson" , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Message-Id: <58bba4310da4c29b068345a4b36af8a531397ff7.1605847196.git.fthain@telegraphics.com.au> From: Finn Thain Subject: [PATCH] macintosh/adb-iop: Send correct poll command Date: Fri, 20 Nov 2020 15:39:56 +1100 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The behaviour of the IOP firmware is not well documented but we do know that IOP message reply data can be used to issue new ADB commands. Use the message reply to better control autopoll behaviour by sending a Talk Register 0 command after every ADB response, not unlike the algorithm in the via-macii driver. This poll command is addressed to that device which last received a Talk command (explicit or otherwise). Cc: Joshua Thompson Fixes: fa3b5a9929fc ("macintosh/adb-iop: Implement idle -> sending state transition") Tested-by: Stan Johnson Signed-off-by: Finn Thain --- drivers/macintosh/adb-iop.c | 40 +++++++++++++++++++++++++++---------- 1 file changed, 30 insertions(+), 10 deletions(-) diff --git a/drivers/macintosh/adb-iop.c b/drivers/macintosh/adb-iop.c index f3d1a460fbce..6b26b6a2c463 100644 --- a/drivers/macintosh/adb-iop.c +++ b/drivers/macintosh/adb-iop.c @@ -25,6 +25,7 @@ static struct adb_request *current_req; static struct adb_request *last_req; static unsigned int autopoll_devs; +static u8 autopoll_addr; static enum adb_iop_state { idle, @@ -41,6 +42,11 @@ static int adb_iop_autopoll(int); static void adb_iop_poll(void); static int adb_iop_reset_bus(void); +/* ADB command byte structure */ +#define ADDR_MASK 0xF0 +#define OP_MASK 0x0C +#define TALK 0x0C + struct adb_driver adb_iop_driver = { .name = "ISM IOP", .probe = adb_iop_probe, @@ -96,17 +102,24 @@ static void adb_iop_complete(struct iop_msg *msg) static void adb_iop_listen(struct iop_msg *msg) { struct adb_iopmsg *amsg = (struct adb_iopmsg *)msg->message; + u8 addr = (amsg->cmd & ADDR_MASK) >> 4; + u8 op = amsg->cmd & OP_MASK; unsigned long flags; bool req_done = false; local_irq_save(flags); - /* Handle a timeout. Timeout packets seem to occur even after - * we've gotten a valid reply to a TALK, presumably because of - * autopolling. + /* Responses to Talk commands may be unsolicited as they are + * produced when the IOP polls devices. They are mostly timeouts. */ - - if (amsg->flags & ADB_IOP_EXPLICIT) { + if (op == TALK && ((1 << addr) & autopoll_devs)) + autopoll_addr = addr; + + switch (amsg->flags & (ADB_IOP_EXPLICIT | + ADB_IOP_AUTOPOLL | + ADB_IOP_TIMEOUT)) { + case ADB_IOP_EXPLICIT: + case ADB_IOP_EXPLICIT | ADB_IOP_TIMEOUT: if (adb_iop_state == awaiting_reply) { struct adb_request *req = current_req; @@ -115,12 +128,16 @@ static void adb_iop_listen(struct iop_msg *msg) req_done = true; } - } else if (!(amsg->flags & ADB_IOP_TIMEOUT)) { - adb_input(&amsg->cmd, amsg->count + 1, - amsg->flags & ADB_IOP_AUTOPOLL); + break; + case ADB_IOP_AUTOPOLL: + if (((1 << addr) & autopoll_devs) && + amsg->cmd == ADB_READREG(addr, 0)) + adb_input(&amsg->cmd, amsg->count + 1, 1); + break; } - - msg->reply[0] = autopoll_devs ? ADB_IOP_AUTOPOLL : 0; + msg->reply[0] = autopoll_addr ? ADB_IOP_AUTOPOLL : 0; + msg->reply[1] = 0; + msg->reply[2] = autopoll_addr ? ADB_READREG(autopoll_addr, 0) : 0; iop_complete_message(msg); if (req_done) @@ -233,6 +250,9 @@ static void adb_iop_set_ap_complete(struct iop_msg *msg) struct adb_iopmsg *amsg = (struct adb_iopmsg *)msg->message; autopoll_devs = (amsg->data[1] << 8) | amsg->data[0]; + if (autopoll_devs & (1 << autopoll_addr)) + return; + autopoll_addr = autopoll_devs ? (ffs(autopoll_devs) - 1) : 0; } static int adb_iop_autopoll(int devs) -- 2.26.2