From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from chaosmail.tech (chaosmail.tech [77.81.229.115]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DC50C1F3BAC; Sat, 11 Jul 2026 22:50:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=77.81.229.115 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783810220; cv=none; b=JgYyjrTnnWaFwRUaHkPR0NfBn/0kO/wFdQ5B3OvsU3ZzR3NYNqKocAd25bGlU8njdJFSjqI281bpiA7q5fvzwqdNfKlgXC+y/itKLtQs1MiAi7nm3Mx5+IgvK/FuBQ87clSUweT9S2SJS5nATZqSFKU84PgqQ7SPKNNWX/2nNXM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783810220; c=relaxed/simple; bh=9hEttOjxUo4x8VZA0u6Zh8it9IZ1e1B/QRSppPFee94=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=LxYlKvy0nfiMrNkOhBhNOavO/Cb16gSlzq2Yrhni2WN1+9OXsCJmEIn0ZC8UHsGUVDwYPgSxitiKtbjb4FKFAlBBMOK8B3H97TxCixMvgFkDO2Yy7NCMVPLPd5CAh7qPN4rsXxf4+9RwCgKZ0dQbJLIbF2oK3LkJrQg2W0wwyzk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=chaosmail.tech; spf=pass smtp.mailfrom=chaosmail.tech; dkim=pass (1024-bit key) header.d=chaosmail.tech header.i=@chaosmail.tech header.b=T3xlR045; arc=none smtp.client-ip=77.81.229.115 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=chaosmail.tech Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chaosmail.tech Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chaosmail.tech header.i=@chaosmail.tech header.b="T3xlR045" Received: by chaosmail.tech (Postfix) id 2256B1C8673; Sat, 11 Jul 2026 22:50:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chaosmail.tech; s=mail; t=1783810207; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=BqTPpzuvZrixISR9QYSmrDSTNk2cgTef1nAy5K2DnE4=; b=T3xlR0454W0UcaNa9HsYGVt63N1K7Vvfn2XsjjAWPW9fTA2Bz4vtxrWWCPBArqroirWByc w6PDEYFcp4SMFyebriPEtY7G7y7NHwSqmIOWB/onHKNjWjcMVA/39mAbIBlCmID5QTZlbX bC72qJ9MPc1pMJlmXyGANLEZeyMinaw= From: Sasha Finkelstein Date: Sun, 12 Jul 2026 00:48:56 +0200 Subject: [PATCH v4] power: supply: macsmc: Support macOS 27 SMC firmware Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260712-gate-power-v4-1-aa59c6583247@chaosmail.tech> X-B4-Tracking: v=1; b=H4sIAAAAAAAC/23OOw7CMBAE0Ksg1xjFG+QPFfdAFP6sEyMgyA4BF OXu2KEBkXKkfTM7koQxYCK71UgiDiGF7prDdr0ittXXBmlwOROogFecMdroHumte2Ck1jsB3Nn KCU8yuEX04TmXHY6fnO7mhLYvDeWiDanv4mteG1i5WyweGGVUag4CWCW5Ffv8S5cuOpw3PdqWl PYBvj38eMjeoeDWKGME+kVff3lQP74u+1uQ2qja11L9+Wma3teBhBI7AQAA X-Change-ID: 20260611-gate-power-cfd726dc0d7f To: Sven Peter , Janne Grunau , Neal Gompa , Sebastian Reichel Cc: asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Joshua Peisach , stable@vger.kernel.org, Sasha Finkelstein X-Developer-Signature: v=1; a=ed25519-sha256; t=1783810207; l=6328; i=k@chaosmail.tech; s=20241124; h=from:subject:message-id; bh=9hEttOjxUo4x8VZA0u6Zh8it9IZ1e1B/QRSppPFee94=; b=7RHM7NDNYULbELZ142reJuoDQRRO402Ewn+zyEZnHcC7TyyVJz9M7AfU8S7PqkuPAeVuvmB+s n9R19EQxBTyC/6f4EFmEQIRIqTJkdvjL0/9ivANdcprnByU9Kcme7hx X-Developer-Key: i=k@chaosmail.tech; a=ed25519; pk=aSkp1PdZ+eF4jpMO6oLvz/YfT5XkBUneWwyhQrOgmsU= The SMC firmware included in macOS 27 changed the size of BCF0 key from 4 to 1 bytes. This key is used for indicating that battery state is critically low. In addition, B0RM key has changed endianness. Reviewed-by: Sven Peter Reviewed-by: Joshua Peisach Reviewed-by: Janne Grunau Cc: stable@vger.kernel.org Fixes: 0ebf821cf6c7 ("power: supply: Add macsmc-power driver for Apple Silicon") Signed-off-by: Sasha Finkelstein --- Changes in v4: - Also fix B0RM endianness - Link to v3: https://patch.msgid.link/20260629-gate-power-v3-1-8428ab93f389@chaosmail.tech Changes in v3: - Minor style fixes - R-b tags and Cc stable - Rebase on 7.2 - Link to v2: https://patch.msgid.link/20260612-gate-power-v2-1-de76cb9bb7ef@chaosmail.tech Changes in v2: - Addressing review feedback - Link to v1: https://patch.msgid.link/20260611-gate-power-v1-1-8a62721086c7@chaosmail.tech --- drivers/power/supply/macsmc-power.c | 52 +++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 45 insertions(+), 7 deletions(-) diff --git a/drivers/power/supply/macsmc-power.c b/drivers/power/supply/macsmc-power.c index ced07f71e0a8..ef735f86394e 100644 --- a/drivers/power/supply/macsmc-power.c +++ b/drivers/power/supply/macsmc-power.c @@ -86,6 +86,11 @@ struct macsmc_power { bool has_ch0i; /* Force discharge (Older firmware) */ bool has_ch0c; /* Inhibit charge (Older firmware) */ bool has_chte; /* Inhibit charge (Modern firmware) */ + /* + * Battery critical key is 1 byte and charge key is little endian + * (Modern firmware) + */ + bool fw_ge_27; u8 num_cells; int nominal_voltage_mv; @@ -273,6 +278,20 @@ static int macsmc_battery_get_date(const char *s, int *out) return 0; } +static int macsmc_battery_read_bcf0(struct macsmc_power *power, u32 *val) +{ + u8 tval = 0; + int ret; + + if (power->fw_ge_27) { + ret = apple_smc_read_u8(power->smc, SMC_KEY(BCF0), &tval); + *val = tval; + return ret; + } + + return apple_smc_read_u32(power->smc, SMC_KEY(BCF0), val); +} + static int macsmc_battery_get_capacity_level(struct macsmc_power *power) { bool flag; @@ -280,7 +299,7 @@ static int macsmc_battery_get_capacity_level(struct macsmc_power *power) int ret; /* Check for emergency shutdown condition */ - if (apple_smc_read_u32(power->smc, SMC_KEY(BCF0), &val) >= 0 && val) + if (macsmc_battery_read_bcf0(power, &val) >= 0 && val) return POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL; /* Check AC status for whether we could boot in this state */ @@ -303,6 +322,12 @@ static int macsmc_battery_get_capacity_level(struct macsmc_power *power) return POWER_SUPPLY_CAPACITY_LEVEL_NORMAL; } +static s16 macsmc_swap_b0rm(struct macsmc_power *power, s16 b0rm) +{ + /* B0RM was Big Endian, likely pass through from TI gas gauge */ + return power->fw_ge_27 ? b0rm : (s16)swab16(b0rm); +} + static int macsmc_battery_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) @@ -397,8 +422,7 @@ static int macsmc_battery_get_property(struct power_supply *psy, break; case POWER_SUPPLY_PROP_CHARGE_NOW: ret = apple_smc_read_u16(power->smc, SMC_KEY(B0RM), &vu16); - /* B0RM is Big Endian, likely pass through from TI gas gauge */ - val->intval = (s16)swab16(vu16) * 1000; + val->intval = macsmc_swap_b0rm(power, vu16) * 1000; break; case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN: ret = apple_smc_read_u16(power->smc, SMC_KEY(B0DC), &vu16); @@ -410,8 +434,7 @@ static int macsmc_battery_get_property(struct power_supply *psy, break; case POWER_SUPPLY_PROP_ENERGY_NOW: ret = apple_smc_read_u16(power->smc, SMC_KEY(B0RM), &vu16); - /* B0RM is Big Endian, likely pass through from TI gas gauge */ - val->intval = (s16)swab16(vu16) * power->nominal_voltage_mv; + val->intval = macsmc_swap_b0rm(power, vu16) * power->nominal_voltage_mv; break; case POWER_SUPPLY_PROP_TEMP: ret = apple_smc_read_u16(power->smc, SMC_KEY(B0AT), &vu16); @@ -577,7 +600,7 @@ static void macsmc_power_critical_work(struct work_struct *wrk) * Check if SMC flagged the battery as empty. * We trigger a graceful shutdown to let the OS save data. */ - if (apple_smc_read_u32(power->smc, SMC_KEY(BCF0), &bcf0) == 0 && bcf0 != 0) { + if (macsmc_battery_read_bcf0(power, &bcf0) == 0 && bcf0 != 0) { power->orderly_shutdown_triggered = true; dev_crit(power->dev, "Battery critical (empty flag set). Triggering orderly shutdown.\n"); orderly_poweroff(true); @@ -616,6 +639,7 @@ static int macsmc_power_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct apple_smc *smc = dev_get_drvdata(pdev->dev.parent); struct power_supply_config psy_cfg = {}; + struct apple_smc_key_info info; struct macsmc_power *power; bool has_battery = false; bool has_ac_adapter = false; @@ -714,6 +738,20 @@ static int macsmc_power_probe(struct platform_device *pdev) if (apple_smc_key_exists(smc, SMC_KEY(CH0I))) power->has_ch0i = true; + ret = apple_smc_get_key_info(power->smc, SMC_KEY(BCF0), &info); + if (ret) { + dev_err(&pdev->dev, "Failed to determine BCF0 key size\n"); + return ret; + } + if (info.size == 1) + power->fw_ge_27 = true; + else if (info.size == 4) + power->fw_ge_27 = false; + else { + dev_err(&pdev->dev, "Unexpected BCF0 key size %d\n", info.size); + return -EIO; + } + /* Reset "Optimised Battery Charging" flags to default state */ if (power->has_chte) apple_smc_write_u32(smc, SMC_KEY(CHTE), 0); @@ -766,7 +804,7 @@ static int macsmc_power_probe(struct platform_device *pdev) power->nominal_voltage_mv = MACSMC_NOMINAL_CELL_VOLTAGE_MV * power->num_cells; /* Enable critical shutdown notifications by reading status once */ - apple_smc_read_u32(power->smc, SMC_KEY(BCF0), &val32); + macsmc_battery_read_bcf0(power, &val32); psy_cfg.drv_data = power; power->batt = devm_power_supply_register(dev, &power->batt_desc, &psy_cfg); --- base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482 change-id: 20260611-gate-power-cfd726dc0d7f Best regards, -- Sasha Finkelstein