From: Vinod Koul Subject: [PATCH v3 6/6] crypto: qcom: Add ACPI support Date: Tue, 3 Jul 2018 11:34:34 +0530 Message-ID: <20180703060434.19293-7-vkoul@kernel.org> References: <20180703060434.19293-1-vkoul@kernel.org> Cc: Bjorn Andersson , Matt Mackall , Herbert Xu , Arnd Bergmann , Greg Kroah-Hartman , linux-arm-msm@vger.kernel.org, Stephen Boyd , Timur Tabi , Vinod Koul To: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: In-Reply-To: <20180703060434.19293-1-vkoul@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org From: Timur Tabi Add support for probing on ACPI systems, with ACPI HID QCOM8160. On ACPI systems, clocks are always enabled, the PRNG should already be enabled, and the register region is read-only. The driver only verifies that the hardware is already enabled never tries to disable or configure it. Signed-off-by: Timur Tabi [port to crypto API] Signed-off-by: Vinod Koul --- drivers/crypto/qcom-rng.c | 37 +++++++++++++++++++++++++++++++++---- 1 file changed, 33 insertions(+), 4 deletions(-) diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c index fdbbcac7bcb8..bc0131d130d6 100644 --- a/drivers/crypto/qcom-rng.c +++ b/drivers/crypto/qcom-rng.c @@ -4,6 +4,7 @@ // Based on msm-rng.c and downstream driver #include +#include #include #include #include @@ -154,6 +155,7 @@ static int qcom_rng_probe(struct platform_device *pdev) { struct resource *res; struct qcom_rng *rng; + u32 val; int ret; rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL); @@ -168,11 +170,27 @@ static int qcom_rng_probe(struct platform_device *pdev) if (IS_ERR(rng->base)) return PTR_ERR(rng->base); - rng->clk = devm_clk_get(&pdev->dev, "core"); - if (IS_ERR(rng->clk)) - return PTR_ERR(rng->clk); - rng->skip_init = (unsigned long)of_device_get_match_data(&pdev->dev); + /* + * ACPI systems have v2 hardware. The clocks are always enabled, + * the PRNG register space is read-only and the PRNG should + * already be enabled. + */ + if (has_acpi_companion(&pdev->dev)) { + val = readl(rng->base + PRNG_CONFIG); + if (!(val & PRNG_CONFIG_HW_ENABLE)) { + dev_err(&pdev->dev, "device is not enabled\n"); + return -ENODEV; + } + rng->skip_init = 1; + } else { + rng->clk = devm_clk_get(&pdev->dev, "core"); + if (IS_ERR(rng->clk)) + return PTR_ERR(rng->clk); + + rng->skip_init = + (unsigned long)of_device_get_match_data(&pdev->dev); + } qcom_rng_dev = rng; ret = crypto_register_rng(&qcom_rng_alg); @@ -193,6 +211,16 @@ static int qcom_rng_remove(struct platform_device *pdev) return 0; } +#if IS_ENABLED(CONFIG_ACPI) +static const struct acpi_device_id qcom_rng_acpi_match[] = { + { + .id = "QCOM8160", + }, + {} +}; +MODULE_DEVICE_TABLE(acpi, msm_rng_acpi_match); +#endif + static const struct of_device_id qcom_rng_of_match[] = { { .compatible = "qcom,prng", .data = (void *)0}, { .compatible = "qcom,prng-ee", .data = (void *)1}, @@ -206,6 +234,7 @@ static struct platform_driver qcom_rng_driver = { .driver = { .name = KBUILD_MODNAME, .of_match_table = of_match_ptr(qcom_rng_of_match), + .acpi_match_table = ACPI_PTR(qcom_rng_acpi_match), } }; module_platform_driver(qcom_rng_driver); -- 2.14.4