mfd: cros_ec: Add API for Fingerprint support

Add API for fingerprint sensor presented by embedded controller.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Fabien Lahoudere <fabien.lahoudere@collabora.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 228 insertions, 0 deletions

diff --git a/include/linux/mfd/cros_ec_commands.h b/include/linux/mfd/cros_ec_commands.h
index 1d0311df44d3..4a9ac3861bdd 100644
--- a/include/linux/mfd/cros_ec_commands.h
+++ b/include/linux/mfd/cros_ec_commands.h
@@ -5044,6 +5044,234 @@ struct ec_response_pd_chip_info_v1 {
 } __ec_align2;
 
 /*****************************************************************************/
+/* Fingerprint MCU commands: range 0x0400-0x040x */
+
+/* Fingerprint SPI sensor passthru command: prototyping ONLY */
+#define EC_CMD_FP_PASSTHRU 0x0400
+
+#define EC_FP_FLAG_NOT_COMPLETE 0x1
+
+struct ec_params_fp_passthru {
+        uint16_t len;           /* Number of bytes to write then read */
+        uint16_t flags;         /* EC_FP_FLAG_xxx */
+        uint8_t data[];         /* Data to send */
+} __ec_align2;
+
+/* Configure the Fingerprint MCU behavior */
+#define EC_CMD_FP_MODE 0x0402
+
+/* Put the sensor in its lowest power mode */
+#define FP_MODE_DEEPSLEEP      BIT(0)
+/* Wait to see a finger on the sensor */
+#define FP_MODE_FINGER_DOWN    BIT(1)
+/* Poll until the finger has left the sensor */
+#define FP_MODE_FINGER_UP      BIT(2)
+/* Capture the current finger image */
+#define FP_MODE_CAPTURE        BIT(3)
+/* Finger enrollment session on-going */
+#define FP_MODE_ENROLL_SESSION BIT(4)
+/* Enroll the current finger image */
+#define FP_MODE_ENROLL_IMAGE   BIT(5)
+/* Try to match the current finger image */
+#define FP_MODE_MATCH          BIT(6)
+/* Reset and re-initialize the sensor. */
+#define FP_MODE_RESET_SENSOR   BIT(7)
+/* special value: don't change anything just read back current mode */
+#define FP_MODE_DONT_CHANGE    BIT(31)
+
+#define FP_VALID_MODES (FP_MODE_DEEPSLEEP      | \
+                        FP_MODE_FINGER_DOWN    | \
+                        FP_MODE_FINGER_UP      | \
+                        FP_MODE_CAPTURE        | \
+                        FP_MODE_ENROLL_SESSION | \
+                        FP_MODE_ENROLL_IMAGE   | \
+                        FP_MODE_MATCH          | \
+                        FP_MODE_RESET_SENSOR   | \
+                        FP_MODE_DONT_CHANGE)
+
+/* Capture types defined in bits [30..28] */
+#define FP_MODE_CAPTURE_TYPE_SHIFT 28
+#define FP_MODE_CAPTURE_TYPE_MASK  (0x7 << FP_MODE_CAPTURE_TYPE_SHIFT)
+/*
+ * This enum must remain ordered, if you add new values you must ensure that
+ * FP_CAPTURE_TYPE_MAX is still the last one.
+ */
+enum fp_capture_type {
+        /* Full blown vendor-defined capture (produces 'frame_size' bytes) */
+        FP_CAPTURE_VENDOR_FORMAT = 0,
+        /* Simple raw image capture (produces width x height x bpp bits) */
+        FP_CAPTURE_SIMPLE_IMAGE = 1,
+        /* Self test pattern (e.g. checkerboard) */
+        FP_CAPTURE_PATTERN0 = 2,
+        /* Self test pattern (e.g. inverted checkerboard) */
+        FP_CAPTURE_PATTERN1 = 3,
+        /* Capture for Quality test with fixed contrast */
+        FP_CAPTURE_QUALITY_TEST = 4,
+        /* Capture for pixel reset value test */
+        FP_CAPTURE_RESET_TEST = 5,
+        FP_CAPTURE_TYPE_MAX,
+};
+/* Extracts the capture type from the sensor 'mode' word */
+#define FP_CAPTURE_TYPE(mode) (((mode) & FP_MODE_CAPTURE_TYPE_MASK) \
+                                       >> FP_MODE_CAPTURE_TYPE_SHIFT)
+
+struct ec_params_fp_mode {
+        uint32_t mode; /* as defined by FP_MODE_ constants */
+} __ec_align4;
+
+struct ec_response_fp_mode {
+        uint32_t mode; /* as defined by FP_MODE_ constants */
+} __ec_align4;
+
+/* Retrieve Fingerprint sensor information */
+#define EC_CMD_FP_INFO 0x0403
+
+/* Number of dead pixels detected on the last maintenance */
+#define FP_ERROR_DEAD_PIXELS(errors) ((errors) & 0x3FF)
+/* Unknown number of dead pixels detected on the last maintenance */
+#define FP_ERROR_DEAD_PIXELS_UNKNOWN (0x3FF)
+/* No interrupt from the sensor */
+#define FP_ERROR_NO_IRQ    BIT(12)
+/* SPI communication error */
+#define FP_ERROR_SPI_COMM  BIT(13)
+/* Invalid sensor Hardware ID */
+#define FP_ERROR_BAD_HWID  BIT(14)
+/* Sensor initialization failed */
+#define FP_ERROR_INIT_FAIL BIT(15)
+
+struct ec_response_fp_info_v0 {
+        /* Sensor identification */
+        uint32_t vendor_id;
+        uint32_t product_id;
+        uint32_t model_id;
+        uint32_t version;
+        /* Image frame characteristics */
+        uint32_t frame_size;
+        uint32_t pixel_format; /* using V4L2_PIX_FMT_ */
+        uint16_t width;
+        uint16_t height;
+        uint16_t bpp;
+        uint16_t errors; /* see FP_ERROR_ flags above */
+} __ec_align4;
+
+struct ec_response_fp_info {
+        /* Sensor identification */
+        uint32_t vendor_id;
+        uint32_t product_id;
+        uint32_t model_id;
+        uint32_t version;
+        /* Image frame characteristics */
+        uint32_t frame_size;
+        uint32_t pixel_format; /* using V4L2_PIX_FMT_ */
+        uint16_t width;
+        uint16_t height;
+        uint16_t bpp;
+        uint16_t errors; /* see FP_ERROR_ flags above */
+        /* Template/finger current information */
+        uint32_t template_size;  /* max template size in bytes */
+        uint16_t template_max;   /* maximum number of fingers/templates */
+        uint16_t template_valid; /* number of valid fingers/templates */
+        uint32_t template_dirty; /* bitmap of templates with MCU side changes */
+        uint32_t template_version; /* version of the template format */
+} __ec_align4;
+
+/* Get the last captured finger frame or a template content */
+#define EC_CMD_FP_FRAME 0x0404
+
+/* constants defining the 'offset' field which also contains the frame index */
+#define FP_FRAME_INDEX_SHIFT       28
+/* Frame buffer where the captured image is stored */
+#define FP_FRAME_INDEX_RAW_IMAGE    0
+/* First frame buffer holding a template */
+#define FP_FRAME_INDEX_TEMPLATE     1
+#define FP_FRAME_GET_BUFFER_INDEX(offset) ((offset) >> FP_FRAME_INDEX_SHIFT)
+#define FP_FRAME_OFFSET_MASK       0x0FFFFFFF
+
+/* Version of the format of the encrypted templates. */
+#define FP_TEMPLATE_FORMAT_VERSION 3
+
+/* Constants for encryption parameters */
+#define FP_CONTEXT_NONCE_BYTES 12
+#define FP_CONTEXT_USERID_WORDS (32 / sizeof(uint32_t))
+#define FP_CONTEXT_TAG_BYTES 16
+#define FP_CONTEXT_SALT_BYTES 16
+#define FP_CONTEXT_TPM_BYTES 32
+
+struct ec_fp_template_encryption_metadata {
+        /*
+         * Version of the structure format (N=3).
+         */
+        uint16_t struct_version;
+        /* Reserved bytes, set to 0. */
+        uint16_t reserved;
+        /*
+         * The salt is *only* ever used for key derivation. The nonce is unique,
+         * a different one is used for every message.
+         */
+        uint8_t nonce[FP_CONTEXT_NONCE_BYTES];
+        uint8_t salt[FP_CONTEXT_SALT_BYTES];
+        uint8_t tag[FP_CONTEXT_TAG_BYTES];
+};
+
+struct ec_params_fp_frame {
+        /*
+         * The offset contains the template index or FP_FRAME_INDEX_RAW_IMAGE
+         * in the high nibble, and the real offset within the frame in
+         * FP_FRAME_OFFSET_MASK.
+         */
+        uint32_t offset;
+        uint32_t size;
+} __ec_align4;
+
+/* Load a template into the MCU */
+#define EC_CMD_FP_TEMPLATE 0x0405
+
+/* Flag in the 'size' field indicating that the full template has been sent */
+#define FP_TEMPLATE_COMMIT 0x80000000
+
+struct ec_params_fp_template {
+        uint32_t offset;
+        uint32_t size;
+        uint8_t data[];
+} __ec_align4;
+
+/* Clear the current fingerprint user context and set a new one */
+#define EC_CMD_FP_CONTEXT 0x0406
+
+struct ec_params_fp_context {
+        uint32_t userid[FP_CONTEXT_USERID_WORDS];
+} __ec_align4;
+
+#define EC_CMD_FP_STATS 0x0407
+
+#define FPSTATS_CAPTURE_INV  BIT(0)
+#define FPSTATS_MATCHING_INV BIT(1)
+
+struct ec_response_fp_stats {
+        uint32_t capture_time_us;
+        uint32_t matching_time_us;
+        uint32_t overall_time_us;
+        struct {
+                uint32_t lo;
+                uint32_t hi;
+        } overall_t0;
+        uint8_t timestamps_invalid;
+        int8_t template_matched;
+} __ec_align2;
+
+#define EC_CMD_FP_SEED 0x0408
+struct ec_params_fp_seed {
+        /*
+         * Version of the structure format (N=3).
+         */
+        uint16_t struct_version;
+        /* Reserved bytes, set to 0. */
+        uint16_t reserved;
+        /* Seed from the TPM. */
+        uint8_t seed[FP_CONTEXT_TPM_BYTES];
+} __ec_align4;
+
+/*****************************************************************************/
 /* Touchpad MCU commands: range 0x0500-0x05FF */
 
 /* Perform touchpad self test */