From patchwork Mon Nov 21 10:48:30 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Martin X-Patchwork-Id: 5230 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id 22DF423E03 for ; Mon, 21 Nov 2011 10:48:59 +0000 (UTC) Received: from mail-fx0-f52.google.com (mail-fx0-f52.google.com [209.85.161.52]) by fiordland.canonical.com (Postfix) with ESMTP id 1047FA183DD for ; Mon, 21 Nov 2011 10:48:59 +0000 (UTC) Received: by mail-fx0-f52.google.com with SMTP id a26so10550775faa.11 for ; Mon, 21 Nov 2011 02:48:59 -0800 (PST) Received: by 10.152.135.179 with SMTP id pt19mr8462619lab.47.1321872538786; Mon, 21 Nov 2011 02:48:58 -0800 (PST) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.152.41.198 with SMTP id h6cs111509lal; Mon, 21 Nov 2011 02:48:58 -0800 (PST) Received: by 10.180.72.146 with SMTP id d18mr13561857wiv.12.1321872537118; Mon, 21 Nov 2011 02:48:57 -0800 (PST) Received: from mail-ww0-f50.google.com (mail-ww0-f50.google.com [74.125.82.50]) by mx.google.com with ESMTPS id v29si4382404weq.92.2011.11.21.02.48.56 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 21 Nov 2011 02:48:57 -0800 (PST) Received-SPF: neutral (google.com: 74.125.82.50 is neither permitted nor denied by best guess record for domain of dave.martin@linaro.org) client-ip=74.125.82.50; Authentication-Results: mx.google.com; spf=neutral (google.com: 74.125.82.50 is neither permitted nor denied by best guess record for domain of dave.martin@linaro.org) smtp.mail=dave.martin@linaro.org Received: by mail-ww0-f50.google.com with SMTP id 14so9540567wwg.31 for ; Mon, 21 Nov 2011 02:48:56 -0800 (PST) Received: by 10.227.198.83 with SMTP id en19mr8437313wbb.26.1321872536467; Mon, 21 Nov 2011 02:48:56 -0800 (PST) Received: from e103592.peterhouse.linaro.org (fw-lnat.cambridge.arm.com. [217.140.96.63]) by mx.google.com with ESMTPS id w27sm12269454wbm.14.2011.11.21.02.48.54 (version=SSLv3 cipher=OTHER); Mon, 21 Nov 2011 02:48:55 -0800 (PST) From: Dave Martin To: linux-kernel@vger.kernel.org Cc: patches@linaro.org, linux-arm-kernel@lists.infradead.org, Dave Martin Subject: [PATCH 2/2] ARM: amba: Auto-generate AMBA driver module aliases during modpost Date: Mon, 21 Nov 2011 10:48:30 +0000 Message-Id: <1321872510-2562-3-git-send-email-dave.martin@linaro.org> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1321872510-2562-1-git-send-email-dave.martin@linaro.org> References: <1321872510-2562-1-git-send-email-dave.martin@linaro.org> This patch adds the necessary support in file2alias.c to define suitable aliases based on the amba_id table in AMBA driver modules. This should be sufficient to allow such modules to be auto-loaded via udev. The AMBA bus driver's uevent hotplug code is also modified to pass an approriate MODALIAS string in the event. For simplicity, the AMBA ID is treated an an opaque 32-bit numeber. Module alises use patterns as appropriate to describe the value- mask pairs described in the driver's amba_id list. The proposed alias format is (extended regex): ^amba:d(HEX){8}$ Where HEX is a single upper-case HEX digit or a pattern (? or [] expression) matching a single upper-case HEX digit, as expected by udev. "d" is short for "device", following existing alias naming conventions for other device types. This adds some flexibility for unambiguously extending the alias format in the future by adding additional leading and trailing fields, if this turns out to be necessary. Signed-off-by: Dave Martin Acked-by: Pawel Moll --- drivers/amba/bus.c | 9 +++++- scripts/mod/file2alias.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 80 insertions(+), 1 deletions(-) diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index bd230e8..a8c598c 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -52,7 +52,14 @@ static int amba_uevent(struct device *dev, struct kobj_uevent_env *env) int retval = 0; retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid); - return retval; + if (retval) + return retval; + + retval = add_uevent_var(env, "MODALIAS=amba:d%08X", pcdev->periphid); + if (retval) + return retval; + + return 0; } #else #define amba_uevent NULL diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index f936d1f..363ab46 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -880,6 +880,74 @@ static int do_isapnp_entry(const char *filename, return 1; } +/* + * Append a match expression for a single masked hex digit. + * outp points to a pointer to the character at which to append. + * *outp is updated on return to point just after the appended text, + * to facilitate further appending. + */ +static void append_nibble_mask(char **outp, + unsigned int nibble, unsigned int mask) +{ + char *p = *outp; + unsigned int i; + + switch (mask) { + case 0: + *p++ = '?'; + break; + + case 0xf: + p += sprintf(p, "%X", nibble); + break; + + default: + /* + * Dumbly emit a match pattern for all possible matching + * digits. This could be improved in some cases using ranges, + * but it has the advantage of being trivially correct, and is + * often optimal. + */ + *p++ = '['; + for (i = 0; i < 0x10; i++) + if ((i & mask) == nibble) + p += sprintf(p, "%X", i); + *p++ = ']'; + } + + /* Ensure that the string remains NUL-terminated: */ + *p = '\0'; + + /* Advance the caller's end-of-string pointer: */ + *outp = p; +} + +/* + * looks like: "amba:dN" + * + * N is exactly 8 digits, where each is an upper-case hex digit, or + * a ? or [] pattern matching exactly one digit. + */ +static int do_amba_entry(const char *filename, + struct amba_id *id, char *alias) +{ + unsigned int digit; + char *p = alias; + + if ((id->id & id->mask) != id->id) + fatal("%s: Masked-off bit(s) of AMBA device ID are non-zero: " + "id=0x%08X, mask=0x%08X. Please fix this driver.\n", + filename, id->id, id->mask); + + p += sprintf(alias, "amba:d"); + for (digit = 0; digit < 8; digit++) + append_nibble_mask(&p, + (id->id >> (4 * (7 - digit))) & 0xf, + (id->mask >> (4 * (7 - digit))) & 0xf); + + return 1; +} + /* Ignore any prefix, eg. some architectures prepend _ */ static inline int sym_is(const char *symbol, const char *name) { @@ -1047,6 +1115,10 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, do_table(symval, sym->st_size, sizeof(struct isapnp_device_id), "isa", do_isapnp_entry, mod); + else if (sym_is(symname, "__mod_amba_device_table")) + do_table(symval, sym->st_size, + sizeof(struct amba_id), "amba", + do_amba_entry, mod); free(zeros); }